Food and Nutrition

Articles relating to food and nutritional needs for hermit crabs.

Color enhancing foods

Oak leaves are rich in tannin - Photo credit Stacy Griffith

Color enhancing foods for hermit crabs.Oak leaves are rich in tannin – Photo credit Stacy Griffith

Great idea for an experiment. I have done some research on colour enhancing foods and figuring out how to get crabs a certain colour.
If you want really dark brown colour hermit crabs then give them lots of foods rich in tannins such as Brown Oak Leaves, Brown Oak Bark (pesticide free). This comes from Carol of CrabWorks. Her hermit crabs have been eating this since they were itty bitty crabbies, 28+ years ago!

If you want orange hues that foods such as carrots, marigold petals have been known to create an increase in orange colour. Foods rich in Astaxanthin are what you are looking for. Do some googling of Astaxanthin and crustacean color/colour.

Plus, I think I may have found a tiny piece of the puzzle as to the ‘blue’ Ecuadorian crabs that have been around.
“The lack of dietary astaxanthin in cultured Penaeus monodon has been shown to be the cause of “Blue Color Syndrome”. After four weeks of feeding a diet containing 50 ppm of astaxanthin, prawns with Blue Color Syndrome resume their normal greenish-brown pigmentation. Analysis of the tissues from the experimental groups verified that the astaxanthin-fed group increased in carotenoids 318% , and had a normal appearance. Those fed the commercial diet without astaxanthin had a carotenoid increase of only 14% and had a blue hue (Menasveta et al. 1993).”
I have heard from many friends in the USA who bought crabs of an unusual bluish hue, that when moulted changed to the standard colours. It was often thought that this was due to some food available in the wild, such as a blue flower of the Galapagos, but it may be that the blue is a sign of lack of dietary astaxanthin. It sounds probable to me! I have contacted some of my favourite biologists about my ponderings and I will be sure to post any information (with permission) to my journal.

For your experiment, it would help if you could take a photo under the same lighting conditions on a regular basis (eg. every week) and create journal entries which have been marked as memories ‘colour experiment’. That way it would be easy to keep track of the changes in exo colour and your observations.

Foods I would offer include:

  • Spirulina
  • Kelp
  • Oak Leaves/Bark
  • Raisins

Note – “Paprika contains the xanthophylls beta-carotene, beta-cryptoxanthin, capsanthin and capsorubin, some of which can apparently be slowly converted to astaxanthin after a lag time. (D’Abramo 1983, Latscha 1991, Wyban, 1996). Preliminary trials demonstrate that supplementation with NatuRose natural astaxanthin yields superior results compared to paprika, as there is no lag time for biosynthetic conversion and it can be directly utilized for metabolic purposes. NatuRose natural astaxanthin is now exclusively used in High Health broodstock to improve larval quality, survival and allow sustained nauplii production (Jim Wyban, personal communication).”


“The color of various carotenoids are related to the number of alternating double-bond pairs in the long polyene chain of the molecule, known as the chromophore (Figure 1). Specifically, light energy is absorbed by the carotenoid polyene system between 400-700 nm, and is converted into vibrational energy and heat, each carotenoid having a unique resonance in this regard. The carrot root contains predominantly (-carotene, which consists of 9 double-bond pairs within the polyene chain, and confers a yellow to orange color. The carotenoid, (-carotene, is composed of 10 alternating double-bond pairs and confers a deeper orange color, whereas the red color of ripe tomatoes and the flesh of watermelons is conferred by lycopene which consists of 11 alternating double-bonds in the polyene chain. Although the polyene structure of astaxanthin is composed of 9 double-bonds similar to (-carotene, the keto and hydroxyl groups of the terminal ring structures contribute to the perceived color through absorption resonance.”
I could go on and on, but I think this will help with the brainstorming process 🙂

What is Astaxanthin?
Astaxanthin is a red-orange pigment that occurs in the natural diets of many aquatic species, including salmon, trout, and shrimp. It is closely related to more commonly known carotenoids such as beta-carotene or lutein. It referenced in the US Code of Federal Regulations Title 21 PART 73—LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION—Subpart A-Foods (Sec. 73.35 Astaxanthin).

Where does Astaxanthin come from?
Astaxanthin isolated from crustacean wastes or produced synthetically. Astaxanthin can also be farmed from unicellular green alga called Haematococcus pluvialis or certain types of yeast and then prepared for commercial use.

Why is it used in commercial aquaculture?
Astaxanthin is added to the feed for salmon, trout, red seabream or shrimp to improve the pigmentation of the flesh or the skin. Salmon and other marine animals cannot make the compound themselves and must get it from their diets This use remains by far the largest market in terms of volume and market value.

Some research suggests that astaxanthin has a number of essential biological functions, ranging from protection against oxidation of essential polyunsaturated fatty acids, protection against UV-light effects, pro-vitamin A activity and vision, immune response, pigmentation, and improved reproduction. As a result, astaxanthin is now also used by some to enhance the immune response of fish and shrimp and to ensure maximum survival and growth.

Is Astaxanthin a safe additive?
It is classified by FDA in a category of color additives called “Exempt from Certification”. The general public often refers to these as “natural” because they are not synthetic organic dyes. Other commonly used “natural” (or “exempt from certification”) color additives include beta-carotene (e.g., carotenoids from sources such as carrots) and anthocyanins (red hued pigments from blueberries and cabbage). To be listed in this category, a color additive must be regarded as posing little or no threat to humans. Currently there is no record of adverse health effects in fish or people consuming astaxanthin.

Health concerns aside, USDA and FDA continue to monitor fish and seafood industry practices to make sure that astaxanthin is not used to pass off one fish species as another. For example, FDA has documented cases in which some disreputable suppliers were offering a fictional variety of salmon called “Salmon Trout” for a much higher price than regular trout. However, as a color enhancer in fish and seafood, the appropriate use of astaxanthin does not present any known health risk to consumers

The lack of dietary astaxanthin in cultured Penaeus monodon has been shown to be the cause of “Blue Color Syndrome”. After four weeks of feeding a diet containing 50 ppm of astaxanthin, prawns with Blue Color Syndrome resume their normal greenish-brown pigmentation. Analysis of the tissues from the experimental groups verified that the astaxanthin-fed group increased in carotenoids 318% , and had a normal appearance. Those fed the commercial diet without astaxanthin had a carotenoid increase of only 14% and had a blue hue (Menasveta et al. 1993).

Adulterants & Additives in hermit crab food

Written by Julia Crab Monday, 01 August 2005


Adulterants & Additives in hermit crab food

What follows is a list of ingredients added to commercial and processed foods that may harm hermit crab health when fed. While I believe that these substances should be avoided, there is no actual scientific proof that these are harmful. This list is being compiled as a guide to dietary harm reduction. The key to good diet, in crabs, other pets, and people, is informed label reading.

Anything enzyme modified *
Anything fermented *
Anything protein fortified *
Ascorbyl Palmitate
Autolyzed yeast *
Barley malt *
BHA (Butylated hydroxyanisole)
BHT (butylated hydroxytoluene)
Bouillon and Broth *
Calcium caseinate *
Copper Sulfate
Enzymes anything *
Flavors(s) & Flavoring(s) *
Gelatin *
Glutamate *
Glutamic acid *
High fructose corn syrup
Hydrogenated or partially-hydrogenated oil
Hydrolyzed protein (any protein that is hydrolyzed) *
Hydrolyzed corn gluten *
Magnesium Stearate
Malt extract *
Malt flavoring *
Maltodextrin *
Monopotassium glutamate *
Monosodium glutamate *
Natural beef flavoring *
Natural chicken flavoring *
Natural pork flavoring *
Protease enzymes *
Protease *
Prussiate of Soda (sodium ferrocyanide)
Seasonings (the word “seasonings”) *
Sodium caseinate *
Soy protein *
Soy protein isolate *
Soy protein concentrate *
Stearic Acid
Stock *
Sulphur Dioxide
Textured protein *
Ultra-pasteurized *
Whey protein concentrate *
Whey protein *
Whey protein isolate *
Yeast extract *
Yeast nutrient *
Yeast food *
* a source of (or possible source of) Monosodium glutamate, or other free glutamates that are just as harmful and have the same actions.

Atypical things hermit crabs can eat

Hermit crabs are omnivorous scavengers in the wild. There are lots of different foods that a hermit crab can eat. We have several different food lists for commonly fed items. Check out a few of the atypical things that hermit crabs can eat:

Feces – herbivorous animal droppings. In Quirimba hermit crabs are known to eat human waste as well.
Fish flakes or pellets
Cuttlebone – great source of calcium
Bonemeal – great source of calcium
Cicadas and their exoskeletons (most other bugs too)
Worm castings

Cicada exoskeletons

Cicada exoskeletons

Compressus eating guinea pig feces

Compressus eating guinea pig feces by Stacy Griffith

Going Natural Beginner’s List

Mini dome sprouter

Going Natural Beginner’s Food List for Hermit Crabs

If you are limited to what organics you can find or afford check out this list of foods that are safe to buy non-organic and foods that you should always buy organic: Dirty Dozen Food List

written by Kerie Campbell

If you’ve decided to get rid of commercial diet completely, and go natural, here is a list of the recommended human-grade beginner foods. These are the highest in nutrition and will make a good base for adding fresh fruit, vegetables and meat too.

Extra Virgin Coconut Oil (olive oil will do in a pinch) for cooking eggs, etc.
Hemp seed meal (very high in HUFAs, and extremely nutritious)
Spirulina (if you can get only one algae product, this alone can just about
replace commercial diet)
Rooibos (high in many nutrients, and vitamin C)
Pure, unprocessed, local honey
Dandelion leaf and root
Flax seed or seed meal
Red raspberry leaf

Add a couple of the following dried flowers or flower products:

rose hips and petals

Add some dried fruit (unsweetened and free of sulphur dioxide or other additives):


If there is still room for more purchases, here is the list I recommend you choose from:
amaranth or quinoa
almonds or walnuts
raw pumpkin or sunflower seed
blue corn meal
kelp powder
wheat germ
chlorella or blue-green algae

The more variety you can provide your crabs, the better they will eat. This list represents the most nutritious foods on the main Epicurean Hermit food list. They will have the highest impact when mixed and offered with fresh foods, and will provide an excellent base for creating homemade crab food.

We highly recommend keeping worm castings and greensand on hand and in your tank daily. Both are highly nutritious and are loved by hermit crabs.

What is it?









shelled hempseed

shelled hempseed

People food for hermit crabs

Plain popcorn is a favorite snack

Plain popcorn is a favorite snack

Aside from the obvious flowers, plants, leaves, fruits and vegetables, there are some other people foods that can be safe to feed to your hermit crabs. This is not an exhaustive list but the most common we come across:

Popcorn – plain (no salt no butter). If you don’t care for plain popcorn you can always buy a small quantity of kernels and pop two or three in the microwave using a paper bag.

Hot dogs – go for all natural and only feed occasionally due to nitrates and other chemicals. No known research on their effects but you should limit the chemicals you are feeding to your hermit crabs in general. Be aware, hermit crabs can get downright piggy over hot dogs and may attempt to bury it for later. This will make your tank moldy and super stinky gross.

Babyfood – this is good if you have a hermit crab that has lost a pincer and is having trouble eating
Unsalted pretzels
Peanut butter – natural, no salt added
Honey – best served in a small dish that the crabs can’t climb into, otherwise you will have a very sticky hermit crab.
Bones – remove the meat if any seasoning was used and then take a hammer and smash the bone so it’s open and the marrow is exposed
Unsalted crackers
Plain cereal – no sugar added
Plain rice cakes
Eggs – raw is probably ok but will be super messy, better to go with scrambled
Egg shells – crushed to a fine powder this is a good source of calcium
Protein – unseasoned: fish, chicken, turkey, beef, pork, tofu
Sardines – look for natural with no additives

Growing your own hermit crab food

With a small seed sprouter and some seeds you can easily grow a mini garden of tasty and tender sprout shoots to feed your hermit crabs. This could be an easy way to provide some fresh food while you are on vacation. If you use some time of eco earth substrate you may be able to get some seeds to sprout directly in the tank, assuming the crabbies don’t eat the seeds before the get going. Sprinkle the seeds on the surface of the substrate and mist them with dechlorinated water each day until they begin to sprout. The crabs will likely start munching on them at this point.

If you prefer to sprout the seeds outside the tank and feed when they get some real growth going, read on!

This is my KEIMLI Mini Germinator Sprouter from bioSnacky. I don’t know that this one is available through US retailers anymore. Other items from bioSnacky A Vogel are available through Amazon (see the widget below).

The small nubs in the bottom are for holding the screen out of the water. Only add water to about half way up the nubbins

Mini dome sprouter

Mini dome sprouter

This is the screen insert that holds the seeds. Place it in the base, resting on top of the nubbins.

Mini dome sprouter screen

Mini dome sprouter screen

Now sprinkle your seeds on the screen. Placement doesn’t matter right now. You can sprout multiple things at the same time. I just happen to have wheat right now.

Mini dome sprouter - add your seeds

Mini dome sprouter – add your seeds

Now you want to turn the screen slightly so the nubbins line up with openings on the edge of the screen and dip it down into the water to moisten the seeds. The seeds will float all over. Lift the screen out of the water and place it back on the nubbins so it is NOT resting in the water. Use your finger to space out the seeds so they aren’t crowded.

Mini dome sprouter - dip seeds in water to moisten

Mini dome sprouter – dip seeds in water to moisten

Now place the lid on the base and find a warm, sunny spot to place the sprouter. Each day change the water and dip the seeds as you did above. As soon as the seeds begin to sprout remove the lid and leave it off. If you see any signs of mildew growing, do not feed the sprouts to your hermit crabs.

Mini dome sprouter

Place lid on and find a spot with gentle sunlight



Hermit Crab Food Recipes

Unfortunately I have no indications as to who may have created this list though I suspect the list came from Kerie Campbell. I know there are

Dry Food Dish

Hermit crab food recipes

endless food ideas but these may help get you started.

Fruity Fish & Flowers II

dried calendula (about 2 tsp.)
dried chamomile (about 1 tsp.)
coconut chunk
large papaya chunk
pink flame rose bud

Kibble and place in the serving dish.

Air-pop about 1 Tbl. amaranth
shred some dulse
1 Tbl. Flott tuna
1 tsp rolled oats
large pinch dandelion root
large pinch dried dandelion leaf.

Kibble and place on top of the fruit dish, sort of a reverse-chutney.

Star Fruit Surprise

Part One: Fruit Salad

1 Tbl. dried pumpkin seed
1 chunk skin-on red delicious apple
6-8 raisins
chunk of old banana
lg. pinch of dried calendula
1 tsp. red clover seed
1 tsp. dried hibiscus flowers
5 sunflower sprouts
1 tsp honey

Kibble, garnish with slice of starfruit.

Part Two: Crunchy Eggs Variant


1/2 eggshell
2 baby carrots
several 1 inch squares of dried nori
1 tsp. hempseed

Cook lightly in coconut oil over low heat until carrot starts to
soften. Add beaten egg and cook gently until just set.

Put in bowl next to Starfruit Surprise, garnish all with some
popcorn popped in coconut oil. Serve!

Copepod Quiche

Preheat oven to 425.

3-4 amaranth graham crackers
1 tsp. melted coconut oil
1-2 tsp. soymilk

Mix well until soggy but still firm. Press into a ceramic serving
dish. I use the Petco ones — you can see them in several of the
pictures in the photo album, approx. 3 inches in diameter and half an
inch deep.

Bake for about 5 minutes, until crust is firming up.

1 egg (discard half to two thirds of the white)
2 tsp. soy milk
pinch of Esprit du Sel (mortared & pestled)
1 heaping teaspoon dried copepods
1/2 tsp. kelp powder
crushed dried jasmine flowers (about 6)
1/2 tsp. rooibos

Mix well, pour into crust. Bake about 8 minutes — it will puff up in
the middle when done — don’t leave it a second longer!

Cut into wedges for number of servings needed. This recipe is

Garnish with 1/2 eggshell and sunflower sprouts.

Lazy Kibble (because I am so tired from my long weekend with Cheyenne I couldn’t be bothered thinking ahead…)

Yesterday’s persimmon slice (nicely leathery by now)
1 Tbl. wheat germ
1 Tbl. sunflower seeds
small mangrove rootlet

Krill Kibble with Chicken Marrow

8-10 thawed krill
coconut chunk
4-6 small blueberries
1 blackberry
1 tsp. dried bladderwrack
1 amaranth graham cracker

Garnish with dried persimmon slice and a smashed open chicken leg bone.

Crabby Joes Mach II

1 Eden Nori-Maki rice cracker
1 coconut chunk
2 cooked clams
3 thawed orange rose petals
3 blueberries
1 tsp. reconstituted arame (sea vegetable)
largish chunk of Semifreddi’s Challah
1 tsp. sunflower seed
1 Krill oil capsule, squeezed out

Weedfish Salad

1 tsp. Flott tuna
3 wilted dandelion heads
1 Tbl. wheat germ
coconut chunk
1/2 orange rosebud

Kibble, garnish with small wedge from extremely old orange, and


small mangrove root ball
1 banana chunk (going black)
1 old chunk of kiwi
1 dried bosc pear slice
1 Tbl. hempseed meal

Fruity Fish and Flowers

In the morning, heat 1/3 cup of coconut milk until hot in microwave
(about 45 seconds at 1100 watts).

Add 2-3 Tbl. barley, and soak all day long.

(In the evening) Kibble together with:

large papaya chunk
coconut chunk
dried persimmon slice
wilted red nasturtium blossom
4 wilted jasmine blossoms
1 pink/red rose bud
1 tsp. chlorella
large pinch red raspberry leaf

Top with thawed silversides, sprinkle with gomasio (sesame seed with
seasalt) and serve!

No name
1 steamed mussel
1 slice blood orange
1 slice uncooked winter squash w/ seeds
1 slice really old kiwi
overblown pink rose

Tonight’s kibble consists of

1 (thawed) yellow rose bud
4 (thawed) krill
3 blueberries
1 raspberry
1 Tbl. rolled oats
1 Tbl. pumpkin seed
1 tsp. kelp powder
1 tsp. honey
banana chunk
1/2 Wasa rolled oats crispbread, broken into bits with mortar and
pestle and soaked in coconut milk for five minutes
1 Tbl. coconut milk


1/2 brown egg shell
2 tsp. Flott tuna
1 large fresh coconut chunk
1 tsp. flaxseed meal
1/2 tsp. four algae powder
1 tsp. bee pollen
1 tsp. rooibus

Mix with raw egg, cook until barely set in coconut oil over very low heat.

Hermit Crab Nutrition Table

Feeding your hermit crab a balanced diet as they would experience in the wild is vital to their ongoing health. We highly recommend keeping worm castings, calcium, and greensand on hand and in your tank daily. Both are highly nutritious and are loved by hermit crabs.

This chart breaks down the nutritional needs and includes some food suggestions.

Hermit Crab Nutrition Table by Lisa L.
Download the chart as a PDF

Also check out Kilimanjaro’s Guide to Hermit Crab Nutrition


The importance of the right kind of salt

written by Jennifer Nielsen

Freshwater aquarium salt is not the same as marine or ocean salt

Freshwater aquarium salt is not the same as marine or ocean salt

The existence of an ocean water dish is a source of great controversy in the world of hermit crab owners. Why the importance of this type of water is rarely debated, it seems that the products used in the creation of Ocean Water are the source of much debate. Just as all hermit crab owners know not to use table salt for their crabs, there are two types of salt available for aquarium use. Fresh Saltwater as well as Ocean Water Salt, which although made of the same components have vastly different role within the world of fish keeping.

A saltwater dish is offered as a means for hermit crabs in captivity to gain access to the ocean with in the habitat. In the wild, a hermit crab would normally crawl down to the sea side to get sea water to help balance the ph/ion levels within their shells. However, in the man-created environment within the habitat, this cannot happen unless a human is providing this type of water. The product used to create this water is of critical importance for this reason, plus in case of injury, salt water is also naturally defecting that will assist in healing of wounds. Hermit Crabs have been known to be seen soaking an injured claw within the salt water pond. Also, molts tend to go a better in the habitats where salt water is readily available.

In order to understand the difference in the product lines, we need to see what Natural Sea Water (NSW) is composed of. The first ingredient is salt of course. However, it also contains about 70 other trace chemicals within it. So while the primary ingredient is in fact common salt (NaCl) there is also several other elements which are key to the composition of Ocean Water. The major components in addition to Chlorine and Sodium are Magnesium, Sulfur/Sulphur, Calcium, and Potassium. Also, common minor components are Bicarbonate, Bromine, Strontium and Silicon. These are considered to be essential to the creation of artificial salt water. This is in addition to other elements, which are in lower amount but found in NSW, such as Chromium, Cobalt, Copper, Fluorine/Fluoride, Iodine/Iodide, Iron, Manganese, Molybdenum, Nickel, Phosphorus/Phosphate, Selenium, Tin, Vanadium and Zinc. Also it is important to note that in the creation of artificial ocean water mixes also tend to be over in Nitrogen/Hydrogen, Nitrate-Nitrogen, Phosphorus as well as Silcon. So offering just one of these elements, such as just the salt, is not truly providing a Salt Water, for several ingredients are missing from the equation.

Now, this is not to say that the salinity level found around the world is stable. Factors such as weather, heat, and location are also factors in the composition of salt water. The Dead Sea is in fact the saltiest body of water in the world. Water located around the equator is also saltier than that which is found in the arctic. While this could be important to different varieties of Hermit Crabs, that is a subject for more research to find out which products mimic different water conditions world wide.

Ocean or Marine salt is required by hermit crabs

Ocean or Marine salt is required by hermit crabs

Freshwater Salt is designed to primarily be a treatment of illness in fish. Specifically, freshwater fish can tolerate low slowly introduced salt in their water. Natural Freshwater does contain salt, but compared to the amounts found in NSW water, the volume of this is significantly lower. Products designed with only this purpose in mind, tend to lack the other elements found in Sea Water. The same is true for cooking salt made from evaporated ocean water. For while the salt is sea salt, it is lacking the other components that make ocean water what it is.

Ocean Water salts, however, provide not only the salt needed but the other components as well. In fact, the label Ocean Water mixes might be a better term for these products because of the fact that they are not just containing one part of the water, but a variety of components that are found in NSW. For the Aquarist who keeps salt water tanks, this is of critical importance to their pets. Therefore, they tend to go with mixes that are more than just salt. In trying to offer Hermit Crabs ocean ponds, it is important that a mix with true composition closest to NSW is used which is why ocean water salt is preferred over Freshwater Salt.

Websites used to provide information in this article are:

Gore on Salinity
Dead Link-Page not Found See archive of webpage here.
Sea Salt mixes

Brands of salt to look for:

  1. Instant Ocean/Instant Ocean Reef Crystals
  2. Oceanic
  3. Red Sea Salt
  4. Fluval Sea Salt
  5. Coralife
  6. Tetra Marine

FAQ A Close Look At Salt Products

Hermit crab enthusiast Jennifer Nielsen compares several brands of sea salt mix in this article.

Instant Ocean and Oceanic Salt Mix for hermit crabs

A comparison of several brands of sea salt mix

Written by Jennifer Nielsen (aka redjln)

While many hermit crab owners realize the importance of providing Ocean Water to their pets, there is a question over which type and which specific product is the best. To answer this, I got Instant Ocean and Reef Crystals enriched blend by Aquarium Systems, Doc Wellfish’s Aquarium Salt, and Aquarium Salt by Jungle. I have gotten a container of Distilled Water to test the products in.

Now, I will disclaim right now that I do not have access to a laboratory of equipment. All I have to test with is a test kit by the name of Marine Master Saltwater test kit. This test kit was not the most expensive, not the cheapest. The test kit can test for pH, Nitrite, Ammonia, and Nitrate. Nitrate/Nitrite is both forms of Nitrogen that is on its way to be coming ammonia. Too much of both of these are deadly to both humans and animals, but are the final stages of the breakdown of waste products from living things. This is a critical part of marine fish keeping, and which is why it was included in the test kit. However for the sake of Hermit Crabs which consume the water, and the fact that nothing is living in this water, testing for pH is the only test that is logical.

What pH is defined as is a measurement of the concentration of hydrogen and hydroxide ions, as well as measures how acidic or alkaline it is. The scale ranges from zero to fourteen. Seven is the ideal number for that is neutral. Less than seven is an acidic solution, and greater than seven is alkaline solution. A good ocean water mix should have between 8.0 and 8.3 pH as that is what the ocean’s pH is. For the sake of this test, I am using this as means to discover if anything else is present in any of the waters.

I also got an inexpensive hydrometer for this testing. What a hydrometer is a means of measuring the amount of salt in water. Natural Sea Water is about 3.5%, yet this is affected by a variety of factors including water temperature. According to my research, marine tank owners tend to want their salinity to be between 1.021-1.024 and since the marine tank owners animals live in imitation ocean water I defer to the range that believe to be best. It has to be tested within a container that allows for the meter to float, which with it being a rather long glass tube posed it own challenges. Eventually I found containers that would work and they were boiled to sterilize them.

For a truly fair test, I decide to use distilled water. Distilled water is water that has no additives in it. Unlike tap or well water which will have minerals or other items in it which I figured could effect the results, I decided to go with as pure of water that I could find.

The first thing about The Doc Wellfish and Jungle products is terms such as “General Tonic and Stress reducers” or “Tropical Fish Treatment or with a remedy” on the packages. The Jungle product even gives a nice set of instructions on how to use this product to clean the tank. Neither the Jungle nor Doc Wellfish products truly give a method of creating ocean water. Which is what the hermit crabs are in of needed. Now the Instant Ocean product just explains that it comes close to being a natural ocean environment. Crystal Reefs also makes the same claims, but that their product also has added calcium.

The looks of the products vary. Doc Wellfish salt is shaped like large crystals. The Jungle Product has smaller crystal. However the Crystal Reef product has tiny crystals and Instant Ocean is a powder. From the standpoint of having to dissolve these products, Instant Ocean would appear to be the easiest to do so with. However, it turns out that all the salts were quickly and easily dissolved, Doc Wellfish only requiring a bit more stirring than the other products in the distilled water.

Now, both Instant Ocean and Reef Crystals give the instructions of a half cup to a gallon of water. There are sixteen cups in a gallon. There sixteen tablespoons in a cup, which meaning eight tablespoons in a half cup. Also there is a ratio of three teaspoons per tablespoon. Now to make a cup of ocean water with these products, I worked out that sixteen cups of water divided by twenty four teaspoons equals about one and half teaspoons. For a cup of water, I would need to use one and a half teaspoons. Now for the Jungle Salt and Doc Wellfish, I figured out that the directions of one tablespoon per five gallons worked out to about less than one-tenth of a teaspoon per cup. Plus, the ratios seemed a bit small, that I was not sure my hydrometer would be able to trace it. So I decided that one quarter of a teaspoon to four cups of water would have to work.

Then containers with the mixtures would also be given a chance to sit overnight to give the salt time to mend with the water and measurements taken. Although the packages claimed that the water would to be pretty much ready to use right away. My research suggested that allowing the water to rest prior to use. Also considering the amounts that most hermit crab owners use, any effects of the ocean water sitting would have an effect. This would show what the levels as if they water had been sitting for a bit. I know that with my thirteen hermit crabs it takes about a week to go through one cup of water.

The first test results were interesting taken after about an hour from the time the water was created. Instant Ocean landed in the center of the 1.020 to 1.030 range. Crystal Reef measured 1.034 to 1.036 ranges. This is higher than the preferred range for salt. Jungle’s salt, in spite of the ratio being higher than what the packaged suggested turned out to be ranking very low salt content of 1.000. Which when I tested my drinking water, is the same amount of this. Doc Wellfish tested to be 1.002. The next day, the hydrometer show no results when I tested the Jungle water. However, the Instant Ocean and Crystal Reef stayed the same with regards to the results I had gotten the day before. I waited a few more days and tried again. The result with Crystal Reef had changed, for the salt level had stabilized within the proper range after four days.

The pH test worked my changing the Ocean Water color. Instant Ocean and Crystal Reef measured a pH of 8.0 after creation and remained stable at this for the next few days. I could not get a reading for the Fresh Water Salt products. They had less than 7.8 pH content in it. The pH for Doc WellFish continued to decrease as well as for the Jungle Product, as I could tell by the color, but was not able to measure with my kit.

I would say the besides the fact the Ocean Water Mixes designed for Marine Tanks do contain more items in it than the products designed for Freshwater tanks. That the fresh water products would require a lot more salt than their packages suggest to create ocean water and are also missing the “something” that cause the pH in the marine products to stabilize. The Jungle Salt even breaks down to not even being in measurable in the water. The fact that Instant Ocean was within range for everything from the start it might be the preferred product to use. Yet, Crystal Reefs could be modified with the addition of some more fresh water to fall within the proper range. However, after sitting four days, it came into range on its own. If I had added the water would have made it back out of range for being too low in salinity.

The main conclusion I came to was that there is something different about the products that are used/designed for Marine Tanks. Something is present in the water that makes the pH stay stable and not decrease. For this reason alone, I advise that people use a Marine Salt mixture, and since most people may not have access to a hydrometer, mix the mixture light so as not to burn the hermit’s gills with too salty of water, considering that tap water also might contain a trace of salt in it.

For further information regarding freshwater salt mixes vs. ocean/sea water mixes that has been recently discovered, please see the end of Ocean Mixes at:
How do I mix ocean water