HCA: Hermit Crab Association

Just got 2 little guys for my son yesterday. They’re so cool! Just setting up their tank today! I did a lot of reading last night, but any advice would be appreciated!

Tank: don’t use anything less then 10 gallon

Heater: buy an under tank heater for reptiles and put it on the BACK. Above the substrate line.

Substrate: needs to be at least 6 inches deep. Use play sand and eco earth and mix at a 5-1 ratio (5 parts sand and 1 part eco earth) must be moistened to sand castle constancy. With de-chlorinated water. NEVER use calcium sand or gravel.

Temperature & humidity: you need a gauge. Digital work best. Must be 80 and 80 before crabs can be put in. The tank must be set up (crab less) for at LEAST a week. For all pets- it’s always recommended to buy EVERYTHING first and set Everything up BEFORE you buy pets.

Diet: hermit crabs are omnivores and eat very little and usually at night. Do NOT feed them pellets. They are full of preserving agents that are likely going to be toxic in the long run. The pet food industry is not as well regulated as it should be and companies can literally put thousands of preservatives in there and maybe mention one on the label. AVOID ALL foods that have more then 5 ingredients especially if the ingredients are very big words that you cannot read. Freeze dried bugs and fruits and veggies are fine as long as they are preservative free.

Water dishes: need 2- and they both must be in the tank at all times. Use declorinator like prime in both and for the salt you need marine grade- like the kind you’d use in salt water tank. Instant ocean is the most frequently used

Sponges: you don’t need them

Few other things

1) hermit crabs molt to grow bigger they dig down & disappear for weeks to months. NEVER DIG UP A BURIED HERMIT CRAB. Make sure you tell your son NOT to go digging

2) Please be aware that you are still then primary caregiver for these crabs.

3) hermit crabs pinch (pinches HURT a lot) And don’t really like being handled.

You’ll also need extra shells natural or polished is fine. NO SPONGEBLOB or other types of painted shells


Sent from my iPhone using Tapatalk

Thank you so much! So far they’re just hiding under the substrate and not moving or eating as far as I can tell. The humidity is a little difficult to keep in the correct range, so we’ve been spraying the tank a few times a day and partially covering the screen top with Saran Wrap and the the humidity goes up to about 80 - 90%.

We’re going away for a few days next week and I’m not sure what I should do. Do I buy a travel tank and set it up with substrate and sand with a heater, thermometer/humidity gauge etc, or leave the crabs where they are and buy a humidifier and leave them with food for a few days. One is buried in the substrate and the other one is laying on top behind a branch.

I know you should never dig up a hermit crab, but I’m worried to leave them alone incase something happens.

Thank you!

Acohen wrote:Thank you so much! So far they’re just hiding under the substrate and not moving or eating as far as I can tell. The humidity is a little difficult to keep in the correct range, so we’ve been spraying the tank a few times a day and partially covering the screen top with Saran Wrap and the the humidity goes up to about 80 - 90%.

We’re going away for a few days next week and I’m not sure what I should do. Do I buy a travel tank and set it up with substrate and sand with a heater, thermometer/humidity gauge etc, or leave the crabs where they are and buy a humidifier and leave them with food for a few days. One is buried in the substrate and the other one is laying on top behind a branch.

I know you should never dig up a hermit crab, but I’m worried to leave them alone incase something happens.

Thank you!

What kind of tank are you using? Did you seal up the lid? It would be more stress on the crabs if your just going away for a few days to put them in a travel container.

Hermit crabs have been molting on their own for years with no help from us.


Sent from my iPhone using Tapatalk

They have a 10 gallon glass tank with a locking metal screen lid. The Saran Wrap doesn’t completely cover the top and I adjust throughout the day according to the humidity reading. I don’t know if they’re molting or just distressing, since they’re new to their environment. Only one is buried and the other one is laying on top of them.

You don’t need to leave holes open on the lid they will get enough ventilation when you open the tank to change the water and food


Sent from my iPhone using Tapatalk

I'm not sure where this is copied from, but it is not all correct/ accurate information, and all of it does not follow HCA guidelines.

Tank: don’t use anything less then 10 gallon
Curly - A ten gallon tank is fine for a couple of smaller crabs. As they grow, you can upgrade. many of us started with ten gallon tanks with no problems at all. HCA guide to crab sizes/ tank sizes/ number of crabs:

viewtopic.php?f=26&t=92541

Heater: buy an under tank heater for reptiles and put it on the BACK. Above the substrate line.

Substrate: needs to be at least 6 inches deep. Use play sand and eco earth and mix at a 5-1 ratio (5 parts sand and 1 part eco earth) must be moistened to sand castle constancy. With de-chlorinated water. NEVER use calcium sand or gravel.
Curly - Your sub can be all sand, all EE, or a mix of the two. Many of us use a ratio of 5 parts play sand to 1 part EE, because it seems to be the easiest for beginners to maintain, it helps with humidity, and it holds it's shape well. Fluker's Hermit Crab Beach sand has 'calcium' in the ingredients, but it is safe (it is one of the few products marketed for crabs that is actually appropriate).

HCA guide to substrate:
viewtopic.php?f=26&t=92542

Temperature & humidity: you need a gauge. Digital work best. Must be 80 and 80 before crabs can be put in. The tank must be set up (crab less) for at LEAST a week. For all pets- it’s always recommended to buy EVERYTHING first and set Everything up BEFORE you buy pets.
Curly - 80/80 is approximate, not set in stone. 75-85% for humidity (higher is okay too). And a tank does NOT need to be set up without crabs for a week, there is NOTHING in HCA guidelines that states this.
Here is the HCA guide re- humidity:
viewtopic.php?f=26&t=92544

Here is the HCA guide for basic crabitat set-up:
viewtopic.php?f=120&t=119273


Diet: hermit crabs are omnivores and eat very little and usually at night. Do NOT feed them pellets. They are full of preserving agents that are likely going to be toxic in the long run. The pet food industry is not as well regulated as it should be and companies can literally put thousands of preservatives in there and maybe mention one on the label. AVOID ALL foods that have more then 5 ingredients especially if the ingredients are very big words that you cannot read. Freeze dried bugs and fruits and veggies are fine as long as they are preservative free.
Curly - There are safe commercial foods, you just need to read labels. You can feed a food with 100 ingredients as long as they are all safe foods for crabs. There are definitely additives that are not safe.
HCA guide to commercial foods:
viewtopic.php?f=25&t=92555

HCA guide to nutrition:
viewtopic.php?f=25&t=92554

Water dishes: need 2- and they both must be in the tank at all times. Use declorinator like prime in both and for the salt you need marine grade- like the kind you’d use in salt water tank. Instant ocean is the most frequently used
Curly - HCA guide to water:
viewtopic.php?f=127&t=92553

Sponges: you don’t need them

Few other things

1) hermit crabs molt to grow bigger they dig down & disappear for weeks to months. NEVER DIG UP A BURIED HERMIT CRAB. Make sure you tell your son NOT to go digging
Curly - There are instances when it is appropriate to dig up a crab, in an emergency such as a flood or bacterial bloom. In general, it is not something that should be routinely done.

2) Please be aware that you are still then primary caregiver for these crabs.
Curly - Please don't preach to members or judge them - everyone is here for help, and we are happy to provide that help.

3) hermit crabs pinch (pinches HURT a lot) And don’t really like being handled.
Curly - While many of us are hands off, there are members who do handle their crabs.

You’ll also need extra shells natural or polished is fine. NO SPONGEBLOB or other types of painted shells
Curly - HCA guide to shells:
viewtopic.php?f=24&t=92552

viewtopic.php?f=24&t=122358