Tag Archive for new

New species of land hermit crab discovered – Coenobita lila

Welcome to the world Coenobita lila!

It’s not often a new species of land hermit crab is announced so this is a pretty big day for us.  Until now the purple land hermit crabs found in Borneo were considered to be C. purpureus AKA Blueberries. This new research document confirms this is false and that the hermit crabs found in Borneo are actually Coenobita lila (for lilac).

Check out the details on the Coenobita hermit crab species site:


New species of land hermit crab discovered: Coenobita lila

Ask Milo – New crab is burrowing

Hermie Newbie asks:

I just got new hermit crab. Now I have two. I have only been a hermit crab owner for a few months. Long story short, I got two from a friend. Anyway one of them died so I got a new one yesterday. He keeps borrowing. Is that normal? Should I do anything about it?

Hi Hermie Newbie,

Yes, burrowing after purchase is very normal. Normally they don’t have the right substrate or substrate depth to do so and really enjoy it when they can. He could be ready to moult or just wanting to recover from Post Purchase Stress.


Please join the Chewin the Choya forum on CSJ and reply to the topic introducing yourself 🙂

Your friend in a pinch

So you want to buy a hermit crab?

Written by Stacy Griffith and originally published on All Things Crabby.com

Hermit crabs

Hermit crabs

Now that you’ve decided that a hermit crab is the pet for you, it’s time to make sure you are right for a hermit crab. If you know as much about hermit crabs as I did when I first purchased one, you are going to appreciate this information. I will cover the basics for setting up a crabitat (a cute name for your hermit crabs habitat). So BEFORE you run off to the pet store and pick out your new pets, print the shopping list at the bottom of the article and take it to the store with you. Once your crabitat is set up properly you can go and pick up your new pets. If you do this correctly from the beginning you will spend less money in the long run.


You need to start with a glass tank with a solid lid. The tank doesn’t need to be watertight. For this reason you can most likely find a tank for free. That’s right, FREE. So many people throw out or give away 10 gallon tanks. I have at least 5 of them I obtained for free. Sources include: craigslist, yard sales, thrift shops, flea markets and pet stores going out of business. I purchased a 20 gallon tank with a stand for ten dollars. I purchased a 40 gallon breeder tank with a lid for thirty dollars. My best find to date is a 150 gallon (that’s not a typo) tank for seventy dollars. There is no reason to buy a brand new tank. Speaking from experience, crabs are highly addictive and nearly everyone wants to own more than can comfortable live in a 10 gallon tank. If this sounds like you, go ahead and find a larger tank now.

Now for a lid. A glass lid is fine but plexiglass/acrylic works just fine also. You can measure the inner lip of your tank and then go to your local hardware store to purchase a piece of plexiglass and have it cut to fit. If your tank comes with a screen lid you can still use plexiglass for a cover and lay it on top, this allows for some venting and additional safeguard against escapes. Many crabbers will cover their screen lid with Press N Seal plastic wrap. If you have the patience to deal with this, it is acceptable. The lid needs to be secured in some fashion, a weight of some sort on top is a good idea. Hermit crabs are avid climbers. They can and WILL escape if you give them the opportunity. Hermit crabs have been seen abandoning their shell in order to execute an escape through a narrow opening. Hermit crabs can use the silicon seal to reach the top of the tank also, and they will. Don’t be surprised if your crabs cling to the underside of the screen lid.

Now we need a substrate or ground covering for the crabitat. I have tried every option currently available save calci sand. The best all around, easy to use, crab friendly substrate is play sand mixed 5:1 with cocofiber. This sand must be the child safe variety and silica free. You should sift through it with a magnet to remove stray metal which somehow finds its way into the sand. Gravel and river rocks are not acceptable as a substrate. Coral sand is expensive but acceptable in water pools or small areas, so long as you provide another medium for burrowing and molting in the tank. Calci sand/Repti sand/Hermit crab sand is not recommended. This sand is sold in small bags and is often brightly colored. This substrate is flat out dangerous. Once it becomes damp it clumps then hardens like cement. I have seen photos of hermit crabs cemented into their shells by calci sand. Substrate should be deeper than the largest crab you intend to purchase by about 6 inches.

The tank must be kept warm so you need a heat source. Commonly, beginners start with under the tank heaters (UTH). This is acceptable but with experience and education, many crabbers will add overhead UVB lighting. Normal cycles of day and light are critical to your crab’s health and well being. Look for a UVB bulb that can be mounted inside the tank, UVB rays are greatly filtered by glass/lexan. UVB is thought to extend the lifespan of a captive hermit crab. A 5.0 reptile bulb is the norm. Heat lamps can be used alone (without at UTH) for heat and light cycle but it is challenging to maintain the correct humidity with a heat lamp. A heat bulb must be turned off at night and second night bulb must be added to maintain heat. The wattage of bulb will depend on your crabitat size and your climate. Minimum tank temperature is 75F but your tank should range from 75-82F (many species like it warmer, closer to 85F). How will you know if it’s warm enough? Well, you will need a thermometer for that. Thermometer strips are not accurate enough. A thermometer with an indicator of some sort is preferable and it should be placed midway down the side of your tank. Your tank should have a range of temperatures so it’s ok if some spots are cooler than others.

The tank must be kept humid. This is not optional, unless your goal is to kill your hermit crabs. This is accomplished by dampening the substrate, placement of water pools or moss. But you must have hygrometer to measure the relative humidity. 70-80% humidity is standard but many species enjoy higher humidity too. It’s important that you remember its RELATIVE and not actual humidity. A gauge style hygrometer can and should be calibrated before placing it in the tank, midway down the side of your tank.

So we have the house built so to speak. Let’s furnish it.


When shopping for fun and interesting items for your crabitat there are some things to bear in mind. Hermit crabs like to climb, a lot. Hermit crabs like to dig and they like to have hidey spots during the day. Purchase items that meet these needs. Avoid anything metal, painted or chemically treated. Bear in mind that the warm, humid climate will be prime for mold and mildew. Non organic items will be resistant to mold and mildew and require less cleaning. Do not go outside and pick up random sticks and things and toss them in your tank. Not all woods are hermit crab safe and you may unwittingly introduce pests to the tank. Trees, plants, flowers are often treated with pesticides, which are lethal to hermit crabs. Fertilizers and other chemicals are not safe. If it’s not organic it shouldn’t be in the tank. Choya/Cholla is safe. Many items sold for reptiles are safe. Creative crabbers convert many household items for their crabitat, don’t be afraid to repurpose items.

The curtains are hung, the furniture is in, let’s eat!

Food and Water

Commonly, hermit crabs have been fed commercial produced food in pellet form. As interest has grown, our knowledge of the dietary needs of hermit crabs has grown tremendously. Rare is the long term crabber who feeds a straight diet of commercial food. The variety of foods that your little scavengers can consume is vast. The rules to remember are: it should be organic and free of table salt. In 2005, the myth that dairy products are deadly to hermit crabs was debunked. Prior to that, the myth that citrus fruits are deadly to hermit crabs was similarly debunked. Do not feed your hermit crabs anything with human table salt added. Not all plants are safe either. There are links at the end of this article and you can find all you ever wanted to know about hermit crab foods on these quality sites. Always feed some form of calcium. This is more important if you don’t have a UVB light.

All species of hermit crabs require constant access to fresh water AND ocean water. The dishes of water should be deep enough and large enough that your biggest hermit crab can wade into the dish and soak themselves and clean their shell. This should be considered in selecting the size of your tank, and the size of the crabs you intend to purchase. Water dishes take up space but they are non negotiable items in your crabitat. Tap water is not safe for your hermit crabs straight from the tap. This does not mean you need to buy expensive bottled water. You need a small bottle of dechlorinator drops. There are water treatment products that remove everything harmful from tap water, one drop per gallon of water. You can find these drops in the fish section of your pet store. You will need to purchase ocean salt to mix ocean water. Typically this is mixed ½ cup per gallon. I am giving you this information so you can determine how large of a package you need. I mix my water in milk jugs. 2018: Change in how to use Prime


Your hermit crabs will molt. They may even molt right after you bring them home (if you use the PPS Minimize the Risk method they will already be in isolation). Hermit crabs dig down in the substrate to molt. You should allow them to do so. Isolation is not required for molting. There are circumstances where you may be forced to place a molter in isolation: another crab is trying to dig up the molter OR you have a surface molter.

So instead of discovering you have a surface molter and running frantically to the store to get the needed items for a isolation tank, let’s just go ahead and get prepared for that now.

An isolation unit should be a miniature version of your crabitat, minus the decorations.
You need substrate but not deep substrate. A surface molter should be left on the surface. You should not attempt to bury the crab yourself. Same for a molter that is being harassed. So shallow substrate is fine. You need a heat source but not a light. For small crabs I like to use the small plastic kritter keepers. I place the molter into the kritter keeper, secure the lid and place the entire box right in the main tank. You will need to cover it to create a dark environment that feels safe to the hermit crab. If you choose this method, no heat source is required.  Buy gauges for your isolation unit if it is to be a stand alone unit. Small kritter keepers placed in the main tank do not require gauges. Smaller food and water dishes are also needed.


Last, but not least, shells. Prepare to become an amateur shell collector. Each crab needs several empty shells to choose from. Do not buy painted shells. They are a waste of money and harmful to the crabs. Buying your shells at the pet store will be more expensive and you will not have a much of a selection. You should do some research online for the types of shells that are popular so you don’t waste your money.

And what will all of this cost me??

Let’s assume you are purchasing everything new, including a 20 gallon tank. Cost will go up with tank size of course.


  • 20 Gallon Aquarium         $ 25.00
  • 2 bags of play sand   $7.00
  • 2 med reptile water dishes    $15.00
  • 1 med reptile food dish    $ 8.00
  • 1 pkg of 2 forest moss bricks    $10.00
  • 1 Glass aquarium lid    $20.00
  • 16 Watt UTH    $40.00
  • 1 Box Instant Ocean    $8.00
  • 1 Bottle Prime water conditioner    $5.00

Approximately $140.00 and that’s without any hermit crabs, a light or spare shells. So much for hermit crabs being a cheap, easy, throw away pet. This may seem like a lot of information but honestly, it’s just the tip of the iceberg.


Substrates for hermit crabs

PPS Minimizing the Impact

Refining the purpose of isolation

Hermit Crab Feeding Guide

Safe and Unsafe Wood for Hermit Crabs

Safe and Unsafe Food for Hermit Crabs

Suitable Shells for Hermit Crabs

What is molting?

Do Hermit Crabs Need a Light?

Global Temperature and Precipitation Maps by Month

PPS (Post Purchase Stress) Minimizing the Impact

written by Sue Latell March 8, 2006

Newly adopted clypeatus

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!


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.

More articles about PPS:

Technique for Adjusting PPS Crabs
Comparative Example for PPS Practices
Preventing Death in New Hermit Crabs

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.

A video on reducing PPS

Technique for Adjusting PPS Crabs – Method

The Post Purchase Stress death cycle created by Mary Milhorn

The Post Purchase Stress death cycle created by Mary Milhorn

This is a (hopefully) more simplified revision of the original.  I have also created a printable calendar for tracking.


The objective of this method is to reduce the impact of physical stress by keeping the hermit crab above ground eating well and exposed to light. Both are vital to the hermit crab’s ability to recover. This is a thirty day method. While this can be accomplished in three weeks, there is no reason to rush. If you are adding new hermit crabs to your existing colony it is important that you do not introduce sick or contagious animals to your healthy colony. Thirty days of observation and quarantine will prevent total colony loss.

Why should I do this?

Do you want your hermit crab to live? With proper care they can live at least 40 years in captivity. Most die within a year. Using this adjustment method to help the crab repair the damage done will improve it’s chances of long term survival.


When planning your trip to purchase your new pets, take note of the temperature and humidity in the store crabitat. If there are no gauges or conditions are unknown we will use a standard starting point.

If these will be your first hermit crabs you can perform this method in the large tank that will be their permanent home.

Each week you will improve the conditions in the isolation crabitat so long as the crab is eating and active.

Normal food may seem foreign after a long time on pellets. Appetite can be stimulated at the beginning by offering greensand and worm castings. Both are highly nutritious and well liked. Popcorn, peanut butter, honey are less nutritious but can be fed as well.

After the first 48 hours there should be some sign of improvement but if not, do not give up.


  • Glass tank with a lid (small tanks are harder to regulate but a 10 gallon is fine)
  • Heat pad
  • Fake plants, logs to climb
  • Thin layer of dry sand
  • Moss
  • EE or shredded coconut husk
  • Fresh and Salt water pools (Treated with Prime)
  • Full spectrum light or at least UVB (12 hours on/off)
  • Digital gauges- must be calibrated
  • Spare shells
  • 2 liter bottle cut in half in case of a surface molt

Do not make the sand deep enough to encourage digging, this can trigger a surface molt.

Do not provide cocohuts or hides, we need the crabs active and where we can see them.

Feeding routine:

Stick to small portions

Change food every day, never leave the day before’s food in the tank with the new food

Do not feed the same food twice in a seven day period

Food that is untouched after 8 hours should be removed and replaced with something new

What to feed:

These are the food groups, and examples of what foods are found within the grouping. Please note that there is overlap in what group these foods represent.

Protein and lipids: this is for energy to grow, forage, reduce competition or minimize cannibalism which more frequently occurs in captivity.

Foods in this class are: meats, fish like silver sides, gold fish, clams, oyster; bone marrow (all meats including poultry), nut meats (many also fall in the omega fats group) salmon skin(including fat). Some vegetation like avocado meat (only) and bamboo stalks. (which also provide Cellulose, high energy)

Carotenoids, Zeaxanthin and cellulose: these foods are necessary to assist the crabs metabolic functions of calcium absorption, processing of minerals, and coloring an individual crab has (darkens pigments). It also improves the crab’s immune system and nervous system functionality.

Foods in this class are: tannin rich leaves, bark, cambium (inner branch skins) of plants like oak, maple, mangrove root, some perennial leaves; fresh fruits and vegetables that are orange, yellow, red or dark green (i.e. squash, sweet potatoes, carrots, natural corn, mango, blue berries, etc); many flower petals (dry), spinach, foliage, bean sprouts, seaweed: spirulina in particular, reptile moss (from pet store) etc.

Carbohydrates: these foods are quick energy foods that will help your crab by immediately fueling them but saving their “stored” reserves necessary for metabolic function.

Foods in this group include: grapes, apple, honey, wheat germ, oatmeal, dried fruit (raisins mostly due to Copper sulfate use in others), banana, pineapple, citrus pulp (inner membrane of skin considered cellulose).

Omega fats: this food group is very important and is totally missed in commercial food formulations unless they are frozen foods! These are necessary for nervous system, exo-skeletal health and processing of carotenoids and other minerals. If there are deficiencies in this group it is typically exhibited by molt death (where you are uncertain), a mildewy appearance to the exoskeleton (they look dehydrated), and they are not active!

Foods in this group overlap protein groups. They include: Coconut, walnut, whole fish (like a dead gold fish), fish skin, animal fat, olive oil, some grass seeds, seeds, peanut butter, etc. There are many of these suitable, some found in fresh flower petals like roses, sunflower, crab apple blossom, etc. Take a look at the edible plants list LINK

Calcium: it is considered superior to provide more than one natural form of calcium! Calcium of course is used mainly for growth of the exoskeleton. Calcium without the support of light and carotenoids will not be properly absorbed by the crab! The acceptable form for supplementation outside of natural forms is Calcium carbonate powder ONLY!

Foods containing calcium, will also provide some proteins as well; here are the main foods ideally used: freeze dried brine shrimp, meal worms, blood worms, krill (fresh, frozen or freeze dried), shrimp tails, sand dollars, powdered oyster shell, cuttlebone, broccoli heads, milk.

How often do I feed from each group?

Protein – everyday

Fruits/Vegetables – 6 out of 7 days

Calcium – 4 out of 7 days

Fats – 3 out of 7 days

Other – 2 out of 7 days

Original method created by Sue Latell in 2008 in collaboration with a DVM and marine biologist.

Preventing death in new hermit crabs

Preventing death in new hermit crabs

Preventing death in new hermit crabs

One of the biggest concerns when buying hermit crabs is early death due to PPS or Post Purchase Stress. The term PPS has been used commonly for many, many years in the hermit crab community. PPS is blamed for unexplained deaths of new crabs. The physical stress occurs mostly PRIOR to your purchase and how many of your new crabs die unexpectedly relies on how much stress was inflicted prior to purchase. The act of harvesting and shipping hermit crabs is very stressful as the crabs are denied humidity, food, water and warmth for long periods prior to shipping and during shipping. They mostly arrive at pet stores dry, hungry, dehydrated and sometimes cold. The last crabs harvested before shipping will be less stressed and more likely to survive. Naturally the opposite holds true for the first crabs to be harvested. Often it takes a period of time for the stress and dehydration to catch up with them but it does and the hermit crab dies. Sometimes it’s a week, or a month but it could take longer. Gill damage from dry air (lack of humidity) can be a slow painful death for a hermit crab.

There are some ways to give your new pet hermit crab the best possible chance at survival. When you purchase new crabs, take note of the store conditions. If there are no gauges, do your best to guess the humidity. When you bring home a new hermit crab, place it in an isolation tank with the same humidity as the store. Use a tiny amount of moss if needed to create the proper humidity. The temperature should be at 72F and remain there. Place a very small amount of sand in the tank, not enough for the crabs to burrow in. Leave the crabs alone except to change food and water. This will allow the crab to relax, destress and get enough to eat and drink. It is very important that your crabs eat well during this time. Food fuels metabolism and this is how they will adjust to the tank settings as you change them. Once you have a consist starting humidity at or near that of the store, hold it there for four days. In four days, add some more moss to bring the humidity up 5%. Continue to increase in this manner until your ISO tank is the same humidity as your main tank. Between the 3rd and 4th week, add more sand so that the crabs can dig down if they want.

If you buy more than one crab, it is okay to place them in the same isolation tank together.

It’s a good idea to closely inspect the hermit crabs before placing them in your main tank. Look for signs of mites or black spots on the exoskeleton. If the hermit crabs have mites (parasites) or black spots on the body, you should keep them quarantined until the mites are gone or they have molted and the black spots are gone. Shell disease is contagious.

If you adopt or purchase hermit crabs from a filthy environment where bugs, flies, maggots are present you should prepare a SHALLOW tray of dechlorinated water and place the crabs right side up and let them walk around. The water should only be deep enough to touch the lower lip of the shell…this will allow some water to swish in the shell and hopefully wash out any parasites or fly larvae. This is really a worst case scenario that we don’t often see but it does happen. If you are rescuing hermit crabs from these conditions be prepared to keep them isolated until you are 100% sure they are free of parasitic mites or other bugs. You do not want to introduce these things into your established tank and hermit crab colony.

Bathing your hermit crabs as a matter of routine is strongly discouraged.

Sue Latell of www.coenobita.org has put together two articles on reducing the impact of PPS in newly purchased crabs. Members of The Crab Street Journal helped conduct the trials on this method and did report a definite change in the death rate of newly purchased crabs. The two articles are linked to each other and also explain the importance of having lights for your crabitat. These are MUST READ articles because they cover a lot of important information.

Refining the Purpose of ISOLATION

PPS (Post Purchase Stress): Minimizing the Impact

This information is based on the exclusive research of Susan Latell, All Rights Reserved.

More articles about PPS:
PPS Minimizing the Impact
Technique for Adjusting PPS Crabs
Comparative Example for PPS Practices
Preventing Death in New Hermit Crabs