HCA: Hermit Crab Association

Since you've come to the emergency forum, we know you want a fast answer to your question. In order for us to figure out the problem as quickly as possible, we ask that you answer the following questions as best you can. Some of them may seem odd, but they're all designed to give us the information we need to give you a good solution for your problem. The things in the [ brackets ] are there to make this post easier to read once submitted. Thanks!


1. What kind of substrate is used in your tank and how deep is it?
A mix of play sand and eco earth about 5:1. At the most shallow part it’s about 10 inches deep.

2. Do you have gauges in the tank to measure temperature and humidity? If so, where are they located and what temperature and humidity do they usually read?
Yes. Temperature is usually between 80-84 degrees F and humidity is usually between 85-95

3. Is a heat source used in the tank? If so, what?
Yes I have a heat mat across the back of the tank. I ordered it from bean farm

4. What types of water are available (fresh or salt) and how is the water treated (what brands of dechlorinator or salt mix and what ratio is used to mix it)?
I buy deionized fresh water for the fresh water bowl and mix it with instant ocean for the saltwater. I’m not home now but I premix water and the instant ocean according to package directions.

5. What kinds of food do you feed and how often is it replaced?
Replaced every other day. I always include some kind of animal protein(chicken, salmon, shrimp, crab, steak, blood worms), one fruit, one vegetable, one herb, one kind of nut or seed, and something for calcium(egg shell and I always have a cuttlebone in the tank). I supplement “things from the sea” almost every feeding aka kombu pieces or spirulina. once a week I add a bit of honey and usually every other feeding I add bee pollen.

6. How long have you had the crab and what species is it, if known?
Around two years. I have one Ecuadorian crab and three purple pinchers


7. Has your crab molted, and how long ago did it happen?
Three just came up from molting within the last two weeks, one is currently molting. 2 out of the 3 who just molted surfaced for a day or so and went back down to explore. So to be clear, just one crab is on the surface currently, but I believe only one is actually molting down there.

8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing?
55 gallon glass tank with a custom made fiberglass lid.

9. How many crabs are in the tank and about how large are they?
4 crabs. Largest is a medium size, two are barley medium, and one is a small. I haven’t measured them in a while but I believe that is current.

10. How many extra shells are usually kept in the tank, if any?
Around 30/40


11. Have there been any fumes or chemicals near the crabitat recently?
No

12. How often do you clean the tank and how?
I usually do a surface sweep once a month or so. For this I use a spoon to scoop out the top layer of soil. I usually clean shells and shell shops when needed, usually once a month I will rinse and boil all shells, wipe everything clean with a paper towel. I remove food bits that are in the sand every other day.


13. Are sponges used in the water dish? If so, how are they cleaned?
No

14. Has anything new been added to your crabitat recently?
No

15. Is there any other information you would like to share that might be helpful (anything that is regularly part of your crab care, playtime, bathing, etc.)?


16. Please describe the emergency situation in detail.


Two weeks ago we got ants in the room the crab tank is in because my boyfriend left ice cream on the window sill. I have read the horror stories on here about ants eating molting crabs to I immediately wiped up all the ants, spread diamoteous earth all over the window sill, around the crab tank, and put cotton balls of cedar wood oil on the window sill. I monitored for ants but I didn’t see anything again until this morning when I changed their food. There were ants all over the cave which holds the fresh water and shells and on another shell shop. They weren’t in the food dish but I think they maybe were eating the crab poop(they always poop in the shell shop haha). I removed the cave and shell shop and killed all of the ants I could see. I had to go to work so I switched the food and added fresh water again. I checked on the tank every ten minutes while I got ready for work and killed any ants that I saw (most times it was just one or two crawling on the outside of the tank near the lid).

So my main questions are:
Do I need to completely disassemble the tank in order to guarantee they are all gone?
Do I need to dig up my molters?
Would it be possible to set up an iso tank for everyone who comes out and keep an eye on the tank until everyone’s above ground and THEN i can redo the sand/move the tank?
Any advice is welcomed as I’m terrified based on what I’ve read on here
.

I wouldn't dig up the molters, that's more dangerous for them than a few ants at this point. Try vaseline completely around the top of the tank (outside) to keep any ants out (yes, messy, but you can clean it up later); kill any ants you see in the tank or on the outside of it (or in the room), and if you can find where they are coming into the room (the window sill?) put strong cinnamon powder there, it confuses their scent trails. If it is the window where they are coming in, try spreading diatomaceous earth all around the ground outside the window; this will kill any insects mechanically (but is not poison, so is safe for dogs/cats/people).

In the meantime, clean up any leftover food in the tank every day rather than every other day, and try feeding only freeze-dried, less scent-attractive food for a few days. It is even fine to leave NO food in the tank for a while, certainly for all the daylight hours of a day, to see if you can stop attracting the ants. And of course, make sure there isn't any food or food wrappers or crumbs or whatever else in the room (not even in a trash can!) that will keep attracting them. You may think ants may not be too disgusting to have in your room, but if there's something that will attract ants, it will also attract roaches, and those carry diseases you do NOT want in your room! Tell your boyfriend to straighten up and clean up after himself!

I would dig them up. I had an ant colony move into my tank and by the time I found them they had eaten half my molters. It was horrific. Ants do not care, and because they can tunnel they will locate anything edible underground. Hermit crabs don't stand a chance against them. Even in the wild, where ants have been introduced and have become invasive species, they are wiping out native land crabs over competition for food and physical attacks.

Definitely listen to wodes; she has more experience in captive crab-keeping than just about anybody. Just a few ants exploring is one thing, but if it's possible they have already established a serious presence in the tank, that does sound like it could be more dangerous than disturbing molters. Just be prepared with appropriate iso's for them. Good luck!

THhank you! I believe it was wodes post where I first heard of this happening. In your opinion, if the molters have ants on them, should I rinse them off? I haven’t been home to check/dig up yet so I just want to be prepared for whatever I find

If you find ants actually on the molters when you dig them up, I suspect it may sadly be too late for them. But if it were me, I would try to get any ants off as gently as I can and put them in safe iso and just see if they survive. Maybe wodes will have more specific ideas in response to this question when she sees it, as she has actually had to deal with this situation before (I've never had anything but a spider or two invade a tank).

Yeah, the ants would need to come off - but because of how they behave you may be able to wait them out and kill them as they flee the crab. They're going to take a mouthful and then travel back with it to their nest. They won't sit and eat away like many predators.

Ok so I just finished digging out the entire tank... honestly I was pretty apprehensive because last night when I got home and this morning I didn’t see a single ant but I figured I wouldn’t ever have peace of mind if i didn’t... and thank god I did!!! No ants, not a single ant in the substrate...

However when I got to the bottom of the tank I had only found 3 out of 4 crabs (two digging, one molting).....
My mind was blown... either I had dug the crab out and put it in the trash with the old sand, or it had escaped at some point...

I found him in the cabinet UNDER the tank!! Oh my gosh I am in shock still! I rarely even leave the lid of the tank open to go refill their water or put their old food in the sink! I can’t believe he escaped and I am so thankful I dug out the tank or I would’ve never found him!!!

hayhay528 wrote: ↑

Sat Dec 21, 2019 4:25 pm

Ok so I just finished digging out the entire tank... honestly I was pretty apprehensive because last night when I got home and this morning I didn’t see a single ant but I figured I wouldn’t ever have peace of mind if i didn’t... and thank god I did!!! No ants, not a single ant in the substrate...

However when I got to the bottom of the tank I had only found 3 out of 4 crabs (two digging, one molting).....
My mind was blown... either I had dug the crab out and put it in the trash with the old sand, or it had escaped at some point...

I found him in the cabinet UNDER the tank!! Oh my gosh I am in shock still! I rarely even leave the lid of the tank open to go refill their water or put their old food in the sink! I can’t believe he escaped and I am so thankful I dug out the tank or I would’ve never found him!!!

Soo happy all turned out well! Glad ya found the escapee too! Lol

Ok so everyone ended up fine but my molters leg didn’t seem to grow back normal one seems like the tip is grown in backwards and another has a curl on the end of it. She has been up eating and walking around so is it safe to add her back into the main tank or should I wait until she has another molt to give her legs a chance to be fixed?

hayhay528 wrote: ↑

Wed Jan 01, 2020 8:15 pm

Ok so everyone ended up fine but my molters leg didn’t seem to grow back normal one seems like the tip is grown in backwards and another has a curl on the end of it. She has been up eating and walking around so is it safe to add her back into the main tank or should I wait until she has another molt to give her legs a chance to be fixed?

If she's doing well you can try to add her back, but make sure to watch over for the first few days and see if the others pick on her or not. That will tell you if she needs to be isolated some more for sure.