Hermit crab’s gills are sensitive to airborne irritants
Land hermit crabs breathe through a modified gill. It is important to protect the gills from strong fragrances, essential oils, candles, household cleaners, chemicals, smoke insecticides and other airborne irritants.
Be mindful of what you spray or use near the crabitat even if your tank is fully sealed. Residual product may still be in the air when you open your tank.
If you are forced to have your home sprayed for insects ensure your tank is fully sealed with saran wrap or something similar. Allow the house to air out at least 24 hours before unsealing your tank.
A member of HCO on FB (not affiliated with LHCOS/CSJ) raised an issue regarding the use of Prime.
After doing some research of our own we are in agreement with their conclusion regarding Prime treated water and pre-mixing.
Please note: As we do not have the necessary information to determine how land hermit crabs are affected by ammonia build up in the water and to what degree we err on the side of caution and treat our water as we would for fish. All information regarding Prime is based on the assumption it is being used in a stable fish tank. Our use is much different. Our primary reason for using Prime is to remove Chlorine and Chloramines and heavy metals from the water and Prime does that well with no recurrence that requires retreatment.
Ammonia build up is only an issue when using semi permanent deep water pools.
You can refer to this link for more information (specifically the comments made by the Seachem staff):
Anyone who premixes water with Prime and stores it for later use
Who this does not affect:
Anyone who treats with Prime at the time of a water change
How do I correctly use Prime:
Standing water dishes/pools:
Change the water entirely every two days. Treat with Prime right in the dish or pool if you wish, swish gently to mix.
Bubbler enhanced dishes/pools:
Change the water entirely twice a week. Add Prime when adding new water.
Filtered semi permanent pools:
Partial water changes every two weeks and retreat the pool. Change ¼ of the water.
Top off the pools as needed and retreat (unless you have a proper ammonia test kit).
Don’t scrub your filters and parts squeaky clean, keep the good bio stuff.
Do rinse everything off with Prime treated water.
To correctly test your water for ammonia build up you will need a good quality test kits. Cheaper kits will not work with Prime and will always read toxic.
Missing both pinchers makes it difficult to eat and protect yourself.
This guide will help you care for a hermit crab that has been attacked, lost several limbs or is suffering from molt complications. General care instructions will be outlined and special exceptions for molting crabs will be included at the end of the guide. If this a newly purchased hermit crab that is dropping limbs you should check out our information on Post Purchase Stress. PPS is a common cause of dropped limbs. Dropping multiple limbs indicates extreme stress. Not all hermit crabs can recover from this type of limb loss.
Isolate
The victim hermit crab needs to be isolated. Use a secure container that other hermit crabs can not access. The victim will remain in isolation until healthy enough to return to the main group. The time in isolation depends on the severity of the attack. A badly injured crab may need to be isolated until the next molt.
The isolation unit should have the same humidity and temperature as the main tank. (Recommended: 80F/80%)
Include a hut or some other place to hide. Shallow substrate, spare shells, food and water are all needed. Each will be discussed below.
In some cases, a small kritter keeper can be turned into an isolation unit and placed in the main tank. With the screen lid secure the other crabs will not be able to harm the victim. This is less stressful as there is no environmental changes for the hermit crab to adapt too. This also allows him to be near his tank mates.
If your crab is also out of it’s shell that needs to be addressed first. Our cup method is tried and true and works in all but the worst cases. Provide 2 or 3 spare shells in the isolation unit once the crab is back in a shell.
Eating well is vital to the recovery process. Commercial hermit crabs foods are 99% unsafe. Most include chemicals that inhibit the molt process and/or are used as a pesticide. We strongly discourage ever feeding commercial foods but feeding them to an already sick crab will only worsen the situation. A natural diet of real food is best.
A hermit crab needs both claws to eat properly. One claw holds the food while the other tears or breaks off a small bit and then brings it up to the mouth. If your hermit crab is missing one claw they can still feed themselves but you will have to alter their diet. Soft foods that do not require tearing or breaking should be fed. Calcium rich foods can be ground into a powder and mixed with another food or fed dry.
If your hermit crab is missing both claws they will have to be hand fed. This means all foods will need to be ground into a powder and moistened slightly. You will dip a toothpick into the food and bring it up near the mouth. The mouth parts should reach down and take the food. If your hermit crab will not eat from you in this way, put a small amount of food in a bottle cap. Position the hermit crab over the cap so they can simply dip their mouth into it.
Change the food daily. Keep the food dish very close to where the hermit crab is resting. This will minimize the need to walk.
A diet consisting of all the key food groups is vital for recovery. Honey can be used to stimulate appetite or give a little boost but it does not have much nutritional value. You can use honey as a base for other foods you have ground up. Kind of like putting ketchup on your kid’s food!
Land hermit crabs can drink water without their claws if they are able to move themselves over the dish. Use small, shallow dishes such as a bottle cap. Keep both kinds of water very close to where the hermit crab is resting. If the hermit crab can walk a bit you can use a wide shallow dish. Change daily or when empty. Water must be treated with Prime or a similar water conditioner.
Substrate
Use shallow play sand for your substrate in isolation. While in normal conditions deep sand is needed that isn’t recommended in this scenario.
Why?
In this situation the crab most likely does not have the strength or ability to dig properly.
The injured hermit crab needs to remain above ground so you can ensure they are eating and drinking.
When the victim is ready to molt again he will be able to safely surface molt in the isolation unit. If he does not move into the hiding place you provided, carefully place it over him. It would not hurt to cover the isolation unit for a few days during the molting process to reduce stress. Shadows passing over the hermit crab signal predator danger, a cover will minimize that additional stress.
Light
Continue to maintain a normal cycle of 12 hours light and 12 hours dark. It is not critical to provide UVB in the isolation unit. If you already have a UVB light set up on the main tank and will be keeping the isolation unit inside the main tank that is fine.
Return to the colony
How will you know your hermit crab is ready to return to the colony?
Are all the limbs regenerated? At the very least your hermit crab needs both claws. This means they will be able to protect themselves inside their shell, as well as feed themselves and climb to escape other crabs if needed.
Is the hermit crab active and eating and drinking normally again?
Able to climb in and out of your water pools unassisted?
If yes to all of the above it is time to return to the main tank. When you do return the hermit crab to the colony do it when you can be around to monitor the tank for a few hours.
Molting crabs
It is rare that a molter will be attacked by tank mates. When this does occur it is a result of incorrect substrate (eco earth only or not deep enough) or a poor diet. The molter needs to be gently moved to isolation and cared for using the above recommendations. Soft crabs should be moved with a clean spoon (or something similar) so that you do not transfer bacteria or other germs to the soft exoskeleton.
A molting crab will be quite weak for a couple days. Don’t expect him to eat or drink in the first day or two. If the exoskeleton was not eaten, it should be ground up and put in a dish with the victim (in addition to the food suggestions above). If the exoskeleton was eaten, provide another source of calcium in the food dish. Remember while underground hermit crabs do not ‘drink’ but they are able to absorb moisture from the substrate if needed. The molt sac is also full of water. Normally the crab would only eat their exo while under but after an attack it is important to get them to eat anything. Don’t force food in the first 24 hours after a molt. Give the crab a chance to eat on their own before attempting to hand feed.
If the molter was wounded and has visible damage to the exo you can treat the spot with our Medicinal Wash for Hermit Crabs if you catch it early. Damage to the exo can cause the outer layers to fuse with the soft under layer. This can lead to difficulties shedding properly during the next molt. This is a very rare time when you may want to move the crab to an isolation unit when you observe pre molt symptoms. This will allow you to monitor the molt process. They may molt perfectly fine in your main tank but if they don’t survive the molt you won’t know for months.
Tips:
Wash your hands before tending to your patient
Use a spoon to gently scoop up the victim. Dig just beneath the crab so there is a some substrate between the crab and the spoon. That will ensure you don’t injure the crab with the spoon.
Let’s look at how to set up a proper hermit crab habitat, which we refer to as a crabitat.
Basing your tank set up on what you saw at the petstore or mall cart where you may have purchased your hermit crabs is a recipe for disaster. Kritter Keepers and wire cages are death boxes and should never be used.
Commonly sold at boardwalk souvenir shops.
None of this junk is safe.
NOT a proper hermit crab habitat. Kritter Keepers are death boxes.
Listed below are the primary components of a proper set up and we will discuss them in detail. If you are not willing to equip the tank properly you should return your hermit crabs or rehome them, they will not thrive without a properly set up habitat. Captive hermit crabs can live over 30 years in the proper habitat. Most hermit crabs die either in the first month of ownership, during the first molt of ownership or within the first year to 18 months. So yes, they can technically ‘survive’ in poor conditions but why on earth would you purposely do this to an animal???
A simple list of the items you will need to properly outfit the crabitat. There are low cost options for most of these items.
Tank
Lid
Light*
Heat
Substrate
Gauges
Bowls
Climbers
Hiders
Plants and Vines
The tank itself should be glass or lexan and large enough to comfortably house your hermit crabs. A MINIMUM of 2 gallons of space per small or medium hermit crab but 5 gallons per crab is much more humane. Large and jumbo crabs will need much more space, 10 gallon minimum. A 10 gallon tank is too small for even one large or jumbo crab. Plan for the future when purchasing your tank, allow for the growth of your crabs or additions to the herd. A used tank is perfectly fine and will greatly reduce the cost of supplies.
The tank must have a lid that retains humidity. A screen lid with glass, lexan or plastic wrap on top is what is typically used. Hermit crabs require humidity to breathe. Opening the lid for feedings and water changes each day usually provides enough air exchange. Fresh air flow reduces mold, mildew and fungus growth.
Light is required, whether they are used as your heat source or not. Hermit crabs require a normal 12 hour cycle of light and dark, it is vital to the molt process. If your crabitat is in a well light room that will meet the need of daytime light. Do NOT place your tank in directly sunlight!
UVB is believed to extend the life span of captive hermit crabs. UVB bulbs must be mounted in such a way that there is no glass or plastic barrier between the bulb and the hermit crabs. Most people mount the lid inside the tank. Bulbs must be replaced every 12 months.
For nighttime viewing, LED in red or blue is safe. Your hermit crabs do not require a light at night.
Hermit crabs require warm temperatures. This can come from overhead lights or from heat pad (often called under the tank heater or UTH) which is placed on the wall of the tank and not under it. Over head lights or heat emitters are not recommended for inexperienced pet owners. They make it challenging to maintain the correct environment in the tank.
Gauges are the only way to monitor and maintain proper heat and humidity levels. The tank temperatures should be a range of 75F to 82F. 72F is the absolute minimum and your tank should not remain at this temperature long term. A temporary dip or spike in temperature is not cause for concern. A range means that your tank should have areas of different temperatures. Some species seem to enjoy slightly warmer temperatures but the common clypeatus is happy in the 75-82F range. Check the substrate temperature as well to make sure it is not too hot. Overly warm substrate will kill molters or discourage molting. Humidity ranges should be 70-80% this is relative humidity. Occasional higher humidity is not cause for concern but maintaining excessively high humidity could lead to flooding or lethal bacteria due to over saturation of your substrate. Your analog hygrometer will need to be calibrated before use. Wireless, digital gauges are relatively cheap and are more accurate than analog gauges.
Substrate should be a mix of 5 parts play sand and 1 part eco earth. The ideal mix will keep the sand moist throughout. The consistency should be so that you could easily make a sand castle. That means that molting burrows will not collapse from drying out. We suggest using a brackish water to expand the eco earth bricks. This will help reduce the chance of mold. The eco earth should be DRY when mixed into the sand so you don’t end up with water logged substrate at the beginning. You can always add water once the crabitat environment is stable, if needed. In many cases it is not needed. Starting with too wet substrate will lead to flooding and/or bacterial blooms. Mix your substrate dry, close up the tank with the lid and all the decor and allow it to stabilize for 48 hours. If the humidity is too low you can mist the substrate. Then wait another 24 hours and check the humidity again. It is much easier to add moisture to the substrate than it is to dry it out once it is in the tank.
The eco earth will help maintain humidity but you may need to add some moss pits if your levels are too low. Not all moss is safe so be sure to check our list: Which types of moss are safe for my hermit crabs?
Three bowls will be needed. Two of the bowls should be deep enough to allow your hermit crabs to submerge themselves. One should be fresh water and one should be ocean water made with marine grade salt mix. All water that comes in contact with your hermit crabs must be treated to remove chlorine, chloramines, ammonia as well as other chemicals. The third bowl will be for food. These don’t have to be reptile dishes specifically but they should be something that your smallest crabs can easily enter and exit. Many people use disposable Gladware type bowls for water pools. We recommend placing a rock, fake plant or coral in the pool for the smaller crabs to climb out.
Places to hide, things to climb on, as well as plants and vines are important to create an environment that is stimulating and enriching for your hermit crabs. Huts do not have to be made of coconut shells, many things will work. The same holds true for things to climb on. There are lots of DIY ideas or less expensive ideas for creating vertical climbing opportunities. Fake plants and vines from a craft store will work as well as the ones you find at the pet store. Some live plants are safe for the crabitat but your hermit crabs will most likely kill them.
Your goal should be to create an environment that is as close to what hermit crabs experience in nature as possible. Hermit crabs live primarily on beaches, so think tropical!
Here are some examples of properly set up crabitats:
Hermit crabs typically go about their molting business below ground away from your prying eyes and nosey tank mates but this isn’t always the case. Sometimes you will find yourself with a surface molter on your hands. Surface molts can be very cool for you but additionally stressful for the crab.
Coenobita clypeatus – Purple Pincer Hermit Crab Surface Molt
C. compressus surface molt. Top most leg is a newly regenerated limb Photo by Nichole Edwards.
Let’s look at the best way to handle a surface molter.
First do not touch or move the crab! (unless you feel you must to ensure it’s safety)
Second find a way to securely isolate the crab.
It is extremely important that your tank temperature and humidity are in the proper ranges at this time.
Do not mist a soft hermit crab, there is danger of causing an infection by over wetting the soft exo.
Do not remove the shed exoskeleton (skin), your molter is going to eat that and it’s important that he does!
Do not place your molter in total darkness. Normal light cycles are needed!
ISO bottle should be pushed all the way to the bottom of your substrate so there is no way for another crab to burrow in from below.
In place isolation of a surface molter can be accomplished by cutting the bottom off of a 2L plastic bottle and then placing it over the molter and pushing it down (gently!) into the substrate, all the way to the bottom of your tank if possible. This will keep tank mates from cannibalizing the molter while it is soft and defenseless. Remove the lid from the bottle top to allow air flow. If you can’t get the bottle all the way to the bottom of the tank, keep an eye out for signs of other crabs trying to burrow their way in.
Kritter Keeper used in main tank as an ISO for surface molters
If you simply can not securely isolate the surface molter, you may be forced to move them. You need to have some sort of container ready, preferably something that can stay in the same tank where the molt has occurred. Very small kritter keepers are ideal for this as they have secure lids but are vented for air flow. As gently as possible move the molter AND the shed exo to the isolation container. Do not poke, prod or otherwise futz with the molter.
Post Molt Photo by Jenny Velasquez
When the molter begins moving around on his own you can gently move him from the 2L bottle enclosure to a larger isolation tank stocked with food and water and a hut. When your molter has fully hardened up it’s time to go back to the main tank. Monitor the molter and the tank mates for signs of aggression. If you witness ongoing aggressive behavior, place all crabs upside down in your water pools. This will rinse off the molting scent and everyone will smell the same again. Unless there is a problem, bathing is UNNECESSARY and should not be done. Aggressive behavior is an indicator of a bigger problem, usually over crowding or inadequate diet.
I understand that it is very fascinating to be able to watch the molt process happening but remember your presence is threatening to the hermit crab at this time. If you want to take photos, do NOT use the flash! Limit your photo taking and time spent hovering and try really hard to let your poor little crabbie do his molting business in peace and quiet.
Coenobita rugosus post surface molt munching on some delicious exo:
We are sorry that you are experiencing a crab care emergency. Below are some links and information to our most commonly experienced emergency situations.
Be aware that the site is not monitored and you may not receive an immediate response from someone. It is in your hermit crab’s best interest that you read the articles linked below.
After reading these items if you still need some help, please locate the list of Emergency Help Questions.
Minimizing the Impact of Post Purchase Stress may prevent hermit crab deaths after purchase
I have belonged to the on-line crabbing community for a little over 3 years now. From day one there was discussion about the number of deaths immediately occurring after purchase. It evolved into a named syndrome: PPS. Many “unexplainable” deaths that occurred in the time-frame from newly acquired to first post molt death were labeled PPS. Time lines wavered (anywhere from one week-up to one year), and alarmingly glossed over (in my opinion) too many other potential causes. The interesting aspect about this subject is that for all the debate that occurred, and the viable, if not absolute reasons offered, not one person or group was willing to agree or offer what to do to minimize it. What is more alarming about this is my own willingness to allow it to continue, even though I understand what PPS is! I think I have been maintaining PPS as an excusable reason for me to have a death in my population. It is important to me to be, or at least appear to be competent in the care of our charges. So grudgingly I have to admit that my complacency in not wanting to clearly define and action PPS, is so that I have a contingent reason to remain blameless for their death. It has been and is treated like this big mystery that there is no obtainable solution to! Well I think it is time to recognize what PPS is, as I am pretty sure we have had the answers at hand for some time!
The purpose of this article is to define what we know PPS to be TODAY; as we can understand its cause and is supported by the knowledge we have documentation for. We can amend standard care practices at this minute. That said, this definition should and will be refined as our successes and information on crabs grows. This is a first step to taking rightful responsibility for this type of crab death. There is a somewhat tested solution to this (if at this point, only by me) that I hope will evolve into an observed and practiced tactic. Please also refer to the companion article: “Refining the Purpose for ISOLATION”, for further clarification.
What is PPS?
PPS is the result of a crab’s inability to physiologically adapt quickly enough from his natural circumstances (environment and habits) into a transitional one and then into a captive environment. The inability to adapt is invoked and influenced by the degree of and withholding of elements the crabs need to adjust to their environment.
This statement means that crabs suffer the most risk of physical stress induced death from the change in their environment (heat, humidity, range and associated resources) by being harvested, shipped and housed by the pet merchants. Resources in this context are water, salt water, food and shelter. Explicitly we need to recognize that the stress is not an “emotional” one, which we have to tendency to relate more easily to. It is physical and involves their ability or inability to forage (for food); have access to resources such as salt water, fresh water; an appropriate substrate and/or room to metabolize to their new environmental surroundings (heat and humidity)! So what factors influence the potential for PPS?
Hermit crabs have remarkable stamina and can tolerate the extremity of their environmental changes for a certain amount of time. They also have built in metabolic processes that assist them in adjusting to their immediate environment. These include hibernation and respiratory regulation. These processes function when fueled appropriately by diet. Because they involve digestion and chemical adjustment, they take longer time to come into effect. Therefore, a rapidly changing environment can short circuit these process mechanisms. Another process, not quite of the same class is osmotic regulation. As long as there is physical access to water, crabs are immediately able to implement procedures to control temperature. This process is mostly reliant on water. A guide to understanding the time frame these processes can take for crabs to implement involves their initial health, their size, and how fluctuant the extremes are in occurrences and interval. All of these things by their very nature are aberrant! For example, a healthy crab can slow down his processes to accommodate a drop in temperature with minimal impact for about 7 days (the rough estimate it takes for a medium sized crab to ingest and process his last meal, plus exhaust immediate reserves). A lower humidity can also be accommodated in similar fashion. Water access does play a significant roll in this control mechanism, as well as for an over hot/humid situation. So if there is a lack of a key resource (water), or if the temperature they are kept at changes rapidly, they may be unable to sustain equilibrium for extended periods of time, especially if the crabs are not fed adequately. This inability does not immediately kill them, but the longer the duration of these types of events accrue, the more they become life threatening. This also explains why a crab may resort to cannibalism to survive!
The hardest part about determining if your crab may succumb to PPS is in the KNOWING if these circumstances were applicable to your crab’s journey to you. Well I can say with some measure of certainty that they would have had to endure significant change over at LEAST a 21 day period. That said, from some of the stories I have read on our forums, that time frame is modest! At some point in the future I will provide a more detailed accounting of what our crabs can go through to get to our pet stores, but for now let’s just focus on PPS.
Here is the really difficult point about PPS, and due to its nature, is probably the main reason we have continued to seek “reasons” outside of our control for PPS. Our NEW CRAB introductory practices! We pride ourselves on establishing and sustaining our interpretation of an “ideal” living environment for our crabs. Temperature and humidity are kept and monitored (by gauge) at the optimum levels (but not always in ranges>>bad, very bad). We for the most part provide the best in foods and offer both types of waters. Provide for hiding, climbing, digging, lighting; what more could our crabs possibly need and want in these circumstances? Why do they still die? Because we in our infinite wisdom think we have provided crab heaven! Well we missed an obvious problem. Not only have some of us taken on the belief that if we provide the right conditions crabs will recover just by what we provide, we have also ignored that crabs have the ability to adjust to their environment when they haven’t already been taxed to very extreme limits. This includes going from BAD environments to GOOD ones! We do not factor in what they have endured before getting to us, and we are quite strict in getting them into good ones as soon as possible. It seems that it is difficult for us even to conceive that we may be pushing them past their endurance level by moving them from that “Crab in a Cup” or dreaded mall kiosk, to a good crabitat set up.
Well in large part we are! We need to graduate them to the ideal conditions so their bodies and processes can catch up. How long can that take? Up to a month, and that is just strictly going by their ability to physically accommodate the change. What fuels that? Food taken in over time, waters and familiarity they gain in their surroundings. Then there is the possibility that they need to molt. Let’s hope they don’t have to for that first 30 day period. In my experience, molters that were new to my tanks suffered the greatest proportion of death! Death resulted 80% more then, than at any other time in my entire 6 year run!! The second month was a bit better at 30% death ratio, but after that it has (at least for me) been less than a 3% chance (at a 50 headcount) after 60 days.
So what are we supposed to do to prevent PPS?
Well while I am tempted to say that a procedure will “cure” almost all potential for PPS, it would be untrue. Since we have absolutely no control over when a crab is collected, or how long it has taken him to be collected, or have the experience to be able to with precision estimate at what point on the PPS scale an individual crab may be at, we have to generalize a treatment. We also cannot accurately factor in how people interpret heat and humidity, healthy diet and other handling aspects involved in overall crab husbandry.
So for the time being, PPS would be best addressed with a method that first allows for close observation by handlers, and secondly accommodates the crab’s ability to adjust to his immediate environment. So what does it take for these conditions to be utilized and what specifically does this mean?
The most important principal is GRADUATION of environmental conditions. Based on an average, calculated by scientists while they studied components of a hermit crab’s anatomical processes, they noted that it can take up to 96 hours for a crab collected and sampled directly from his native habitat to adjust to a change in environment. This is once the crab reaches his physiological threshold whereby hormonal triggers begin to occur. The hormonal regulation is fueled mostly by the crab’s food resources, but it also can include other regulatory systems. This means that a crab requires time to reduce physical stress by being able to adjust to his immediate circumstance. The greater the change, the less potential a crab has to adjust successfully, and co-dependent to time is the resources available to the crab either internally (through reserves), or externally in the form of food and water. Scientists have calculated that there is the highest successful adjustment when environmental changes occur in 5-7% increments. This means if they are adjusting temperature or humidity, they use the existing conditions as the constant, and use the percentage as the increment for adjustment. So how do we apply that to our method of introduction? By this:
1. Observe and recognize that your crabs are mostly leaving poor humidity and heat conditions. (Usually too high/low heat, and too low humidity) Also, food resources have probably (but not always) been limited, thus making the crab’s system “sluggish” and slow to respond to the change. See if they have had water vs. a sponge; note the approximate heat and humidity conditions and think of them in comparative terms to the ideal. Then establish a threshold (minimum tolerance level), that will be your starting point for readjusting crabs to the acceptable ranges.
This is not an exact process, because as you can already see, there can be several variables. I will provide an example, and after that I am afraid it will remain for the time being a function of trial and error, until we have more data in respect to successful outcomes. We will be measuring this by people providing key data that will be stored in a database. Once we tabulate “samples”, the increased number of samples will provide more accurate standards that we can provide as procedure to future situations.
2. We must utilize ISOLATION in a separate tank, where the environmental factors of heat and humidity is not PRESET at the ideal conditions. I have been concerned lately in the shift of thinking regarding the necessity of Isolation as part of the procedure for introduction. Far more focus has been placed on ISO being utilized for MOLTING. What I find frustrating about this, is that it is NOT necessary to do so in most circumstances. For re-acclimatizing stressed hermit crabs, it is! Please read the companion article “Refining the Purpose for ISOLATION”.
This is the sector where in the past I had remained flexible in terms of the duration of time we keep new crabs in isolation. That was when I was looking at it strictly from the perspective of general health and potential for bugs. What I was remiss in communicating, is that I have always as a practice kept new crabs in ISO for at least a month. In fact, it was rare that I move one to the main tank earlier even though they showed no indication of stress or contamination. The other important aspect of my ISO tank is that it is NOT at the same range in heat and humidity as my main population tanks. This was not immediately intentional; it came about from not being used! Why heat and humidify an empty tank?
Many of you already know that I do not advocate removal of pre-molt or molting crabs to isolation. So really my ISO has really only served as the transitional tank for new crabs, or as the treatment tank for sick ones. I think that initially this is why I had fewer occurrences of PPS, without knowingly doing it. My ISO built up to the ideal and equivalent main crabitat conditions over the period of time I kept them in ISO. I did not see the relationship until I consulted Peter about overheating issues and about dropped limbs. This was in early 2004. Principally what I learned about dropped limbs is that it was due to a stress induced shock caused by an extreme environmental change (that aspect was speculated and communicated already) and was just confirmed. The new information was that by controlling the extremity of the change, we would allow the crab to metabolically adjust less stressfully. It was outlined to me that changes in humidity and temperature should be gradually increased in percentage and in time to assist the crab. Or, at the very least , recognizing WHAT the differences in the crab’s initial environment were and adjusting the new conditions in relation to IDEAL conditions. I have shared this several times, especially when it was clearly explained by the owner how poor the previous conditions were. Consider this rationale: Remember reading at least once a story relating how a crab was able to survive DIRE conditions for up to a year and survive, only to die within weeks of being introduced to a “perfect” environment? Wouldn’t it stand to reason that the crab evolved to adjusting to his conditions to subsist in his environment if it occurred over an interval of time that his body could adapt to? Then we basically eliminated that interval to reverse the process, thus resulting in death. I saw immediately why this could be possible. Now you may understand too why I have been harping on maintaining “ranges” of temperature and humidity. It is because it can maximize the crab’s ability to adjust!
3. We must set a starting point for environmental conditions. If your crab comes from a pet store that has for example a heat lamp, no cover, no water, chances are that the approximate existing humidity range is 50% or lower. ASK how long the crabs have been in the store tank. If it has been more than 2 days, you will need to start at the lowest level that crabs can tolerate. That is 60% (with access to water and food), and a maximum tank temperature of 72 degrees. You would keep that level for a period of 72 hours and then increase it by 10% to 66%, and maintain that level for 72 hours, repeating the process until you match your main tanks average humidity level. This would take roughly 2 weeks if your target range was 79%. During this time crabs will need food to support the hormonal adjustment necessary to acclimate. Give them the fighting chance by not immediately moving them into a more competitive environment with your existing and healthier crabs! By sticking new crabs into a main population without benefit of isolation during their adjustment, you are diminishing the new crab’s ability to recover by increasing the resource competition level.
Temperature is not as significant to worry about; crabs use osmotic processes to control that! So their only need there is access to ocean salt water. It is the hormonally, or more accurately, the metabolically related processes that helps a crab adjust to humidity, and for that they need fuel and the time to process it. In effect this is how to minimize PPS.
Why is this not a fool proof cure?
This is the question that has held me back for some time. I wanted a definitive answer as to why PPS happened. It wasn’t until I looked at it in components that it became clear that while we can significantly reduce PPS, there will be circumstances that cannot be overcome. The ones I understand the most are:
1). Damage to gills from prolonged dehydration –
This condition thankfully is not too common, surfactants that the crab regurgitates from his digestive tract in order to self hydrate his gills, ultimately will result in death. There is nothing we can do if the conditions he endured drive him to this point.
2). Starvation-
While this seems to be one of the things we can combat more readily, if it has endured for a prolonged period of time, we may not be able to reverse the effects. A crab requires constant energy to sustain his metabolic changes. He may not be able to produce the necessary hormones to transition into his new environment. What’s imminently worse about this condition is that it can result in death for a crab that needs to molt, and remains a potential for causing molt death more typically, but not exclusively (depending on the crabs size) for the first few months of ownership.
3). Our humidity and temperature control-
Okay, I am prepared to deal with the flack I will get for blaming owners who fail to recognize the importance of maintaining temperature and humidity ranges. But there it is! There is an inherent mistake created when we relate heat and humidity in absolute terms! When we reply to inquiries with a comment like “set your heat and humidity to 80/80 and you can’t go wrong”, well, we do! While 80/80 is within the tolerable ranges, it does not communicate that these settings are the higher end of the range, and that there is and should be other temperatures and humidity levels within the crabitat. I realize that this occurs more out of a convention of speech and is not meant to mislead people. The sad reality is that people (especially new crabbers) take these stated levels literally and they worry and painstakingly try to achieve this exact ratio. What worries me about this is that we need to recognize AND COMMUNICATE that a crabitat should have RANGES of heat and temperature. The people saying that 80/80 produces active healthy crabs are not totally wrong (I just hate the way it is expressed because it gets misconstrued)…it is the “Way” it is interpreted when we use such an explicit example. We cannot show that the loftier areas will be lower in humidity but higher in heat…just like the middle of the tank will be closer to the true 80/80…and that the lower regions will be even more skewed temperature wise over the UTH (if there is one), below the lamp etc…so how can we communicate these acceptable ranges without creating a pseudo class that people use really by convention of speech and lack of full understanding how humidity and temperature work? It gets into dangerous ground when we say “oh Straws like the humidity at 85%”…well many of us do not segregate our tanks by species…and an E or PP may overheat when a tank is that over saturated!
I feel this aspect contributes greatly to crab death in general, and not just from the PPS perspective. Though it is related in the sense that we diminish our crab’s ability to adjust by not providing differences that our crabs can utilize! They are in a tank people! There is no comparison to their natural habitat where there is wind and tidal influences, ground cover, and the fact that they can move to utilize these resources at their whim, and instinct! We NEED to provide for that! I trust my own experience in this, and I admit I have never had an “unexplained” death 6 months to 1 year after getting them. So rather blatantly, I don’t think it is acceptable to define PPS over such a broad time-frame! I have had a couple of puzzling deaths, and I attribute it more to me not providing them with the proper foods, or the proper balance of adequate diet, and maybe even possibly poisoning them, than the soon to be dispensed idea that it is PPS! We need to call a spade a spade, or we are in danger of remaining blissfully, and BLAMEFULLY ignorant of real issues that we could resolve! I am ashamed that until a short while ago, I was willing to ignore the significant realization that WE are a component of PPS. I trust the results I have had over the years, and have now filled in the reasons (started by dumb luck, and now more understood) due to valuable information I learned from reading and discussing with experts the physical processes our crabs are capable of. Now it is time to use the information and change our methods!
So what will the new time defined extent of PPS related deaths be?
For now, until we amass actual numbers, I think my model that I accrued when taking in adopted crabs, and purchased new crabs will be used (a total of 117 over 2 years). That means that potential PPS deaths will defined for at least 30 days from original ownership date up to and including the first molt. This will be conditioned by the fact that if a molt occurs after the first 60 days (being the highest risk for PPS related death), then the death may be more attributed to a lack within the owners environment, not necessarily PPS. The factors used to qualify these latent molts will be crab size and review of the owner’s food list and environmental conditions!
Overview:
PPS is Death as a result of a crab being deprived of the conditions and resources he needs to adapt to changes in his environment. We are part of that change. We can minimize PPS death by practicing ISOLATION and a GRADUATED increase to ideal crabitat conditions over a period of time to offset the poor conditions crab harvesting can create. These changes should occur in stages that the crab’s physical processes can accommodate. We need first to acknowledge the crabs own capability to adjust, and synchronize the environmental adjustments to their metabolic time frame. Death of a crab should not be classified as PPS outside of the initial established time frame of adjustment (30 days), unless there is a molt occurring within a 60 day time frame. After 60days, a case by case assessment should be done, and evaluated based on the crab’s size, on the conditions he came from, and from the examination of existing diet and environmental factors (heat and humidity). While PPS will be definite within the 30 day period, that likelihood in classification diminishes as time increases.
Implementation Recommendations:
This definition will be amended by statistical evaluation, and new study material. I recommend review in the process be conducted in 90 days time and that a committee be established in evaluating collected data. A permanent template with fixed element names should be used to feed the database for this data collection category: PPS.
Concurrent to this study, an evaluation of the specific accepted time frame for PPS to be considered a cause should be presented to crab care communities by poll. It should be encouraged that members also support their choice with their personal reasoning. This will then be used to help the committee establish the recognized and formally accepted time interval for decreeing PPS as the cause of death.
Offering greensand and worm castings is recommended at well. When hermit crabs won’t eat anything they will almost always eat both of these highly nutritious foods.
Isolation by very general definition, in the crabbing world means to keep crabs separated from each other in groups or by individuals by means of an object such as another tank. It can also mean that one crab can be isolated within a crabitat by an object such as a bottle or CD case, or piece of plastic. The purpose for this division is multiple. Most commonly, isolation has been utilized when dealing with crab illness, contamination, surface molting and more often than I like to see, molting in general. What ever happened to using it for NEW crab introduction? This was at one time, the main reason to have isolation. It was a measure to ensure a crab’s health and stability before subjecting him to competition in a larger population of crabs. This purpose will be my main focus! First let’s address some noted trends.
Comparative Example for PPS Minimization Technique
Little Billy has had 3 hermit crabs since his 12 birthday. He has a 20 gallon tank housing his 3 small PP crabs. One day when he is at the store picking up some ocean salt water for his crabs, he spots a tank containing 2 poor little Ruggies that have no water except for a damp sponge, huge pellets of food that he doubts they have even attempted to eat, and no ground cover to protect them from the 100 watt heat lamp that is shining directly on them from an open tank top. Billy has been a very conscientious crab owner. He explored on-line information on how to care for hermit crabs and has all the bells and whistles to keep his crab people happy. He has proudly seen his crabs molt, grow and prosper for the past year. Billy knows that the little Ruggies will not last long in the current conditions they are in. He consults a clerk, advises her of the poor crabitat conditions, and notes that there will likely be no changes made based on his advice. Billy’s mom is a sweetheart and lets Billy rescue these poor crabs from their sorry condition. Billy finds out from the cashier that those are the last ones from their shipment last month, and now they can order more. (God forbid). Billy provides his new crabs with a dip into his tanks water dish, and then they scurry to hide in the handy cave he has for his crabs. Well, a week later, and Billy has still not seen his new crabs. He doesn’t think they have even been to the food dish. He isn’t too concerned since they are likely de-stressing in the wonderful conditions in his tank. Well a couple of more weeks pass. Billy thinks he seen one of his new guys in the water dish, now there is signs of digging, this crab must be molting. Well another couple of weeks lapse, and it is now high time to do a deep clean. Billy carefully digs around to see if he can locate where his crabs may be down molting so he proceeds cautiously. Billy takes out some of his plants and shells for rinsing, he has found the top of one of his new crab’s shells, he checks to see how the little guy is faring and discovers that it has died. Billy is heart broken. Finally the entire tank is unearthed and Billy discovers that neither one of his new little ruggies made it!! That darn PPS, it is just not fair!
After your crabitat is set up you will have to maintain it and your crabs. Below you will find a list of what tasks should be done daily, weekly and monthly.
Daily
o Refill fresh water dish and the ocean water pond
o Empty and clean the food dish (no chemicals)
o Offer a different food each day
o Check the humidity level is 70- 80% relative
o Check the temperature level is near 80F and that it is stable
Weekly
o Clean the bowls and dishes (without chemicals)
o Pick through the substrate for food and feces (isopods and springtails can help with this)
Monthly
o Where needed, remove all items from tank (substrate, wood, toys, dishes etc) and clean by boiling or baking. Usually only needed if you have unwanted mold or mildew.
o Wipe down walls of tank with vinegar and water, or ocean water mixture. (Avoid cleaning chemicals eg. bleach)
o Sterilize (boiling) seashells and re-offer them to crabs
The Definition of Isolation
