Lethargic and not eating

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Lethargic and not eating

Post by shawneeh » Sat Jan 05, 2019 7:32 pm

Hi all,
I'm very worried about Tiny, our 2 yr old Hermie. He isn’t moving around and is acting lethargic. Today he seemed to be practically lying on his side. When I opened the lid and checked on him, he did sit up normally. But he doesn’t seem well.

He was doing fine until we brought in Biggie Big about 4 weeks ago. Biggie is a lot bigger than Tiny (Tiny used to be the largest of 4, but he’s been alone for about 6 months - different story).

There’s 2 things I’m suspecting:
1) When Biggie came (a rescue) my husband put him in the tank in a large cage to keep him separate for a bit from Tiny but with the top off and Tiny crawled in the cage the same day. The next day I smelled a terrible ammonia smell. I removed Biggie's cage, which turned out to be the source (so bad) and the smell left the tank about 1-2 days later. Biggie is doing great. Maybe the smell did something to Tiny? (In retrospect I should’ve washed Biggie before putting him in.)

2) Biggie and Tiny seemed to be establishing dominance at first but I saw no aggression at all and never have. Just antenna feeling and crawling over each other. And that was only the first few days. Still, I wonder if there was a fight of some sort and Tiny got hurt and is recovering. I can’t tell if he’s injured but he can walk fine. I haven’t seen him have any food or water since Biggie came except one time I saw him in the dish of crushed eggshells, which made me wonder even more if he was hurt and craving calcium. Biggie is often near Tiny, cuddled up behind him.

I don’t know what to do to help Tiny but he definitely hasn’t been right since Biggie came in. Not eating/drinking far as I can tell and not moving if he can help it. He will walk if spooked, and seems to do so fine. I’ve noticed he’s moved from one hiding spot to another about 2-3 times. Biggie seems to always want to be near Tiny, cuddled up behind Tiny's shell. Again, he doesn't seem aggressive. Biggie is always moving around, eating, exploring. But not Tiny.

Should I separate them by putting Tiny in a cage for a while? (I don’t have 2 tanks set up.)


Here’s my template:

1. What kind of substrate is used in your tank and how deep is it? Sand and cocofiber, about 4” 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 - humidity is 72-80%, temperature is about 80.

3. Is a heat source used in the tank? If so, what? Yes, several pads stuck to sides.

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)? Fresh dechlorinated water and bottled salt water from PetSmart.

5. What kinds of food do you feed and how often is it replaced? Powdered crab food from Rehoboth, DE where I got Tiny, and he’s always liked it. Also give fresh food about 2-3 times/week. Replace it about ever other night.

6. How long have you had the crab and what species is it, if known? Had Tiny for about 2 years. He’s brown with a purple claw, not sure what kind.

7. Has your crab molted, and how long ago did it happen? Yes, many times. Though he’s been down several times, he's kept the same shell for about a year. Sometimes tries on a new one but goes back to the old. He needs to be in a new shell. There’s plenty to choose from.

8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing? 20 gallon, glass lid.

9. How many crabs are in the tank and about how large are they? 2 in tank. Tiny is about 2” and Biggie our new rescue is about 3” more or less.

10. How many extra shells are usually kept in the tank, if any? About 10. Biggie has tried all sorts of shells on.

11. Have there been any fumes or chemicals near the crabitat recently? Yes – ammonia when Biggie first came but none since.

12. How often do you clean the tank and how? Not often. I did a thorough clean about 3 mos ago.

13. Are sponges used in the water dish? If so, how are they cleaned? I just put one in. To clean, I just rinse it out.

14. Has anything new been added to your crabitat recently? Yes, Biggie Big the crab.

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Re: Lethargic and not eating

Post by curlysister » Sun Jan 06, 2019 2:19 pm

It may or may not have been the fumes. There are a few things in your set up that could be improved.

Your humidity is a bit low, it's best over 80%.

You need a bit more substrate, it should be a minimum of 6 inches, or three times as deep as your largest crab, whichever is deeper. Is it moist enough to hold shape (ie- sand castle consistency)?

What brand of dechlorinator do you use? The salt water from Pet Smart - is it aquarium salt or marine salt? Most pre-mixed salt water is aquarium salt. Hermit crabs need marine salt. Most of us use Instant Ocean, which we mix with our dechlorinated fresh water to make salt water.

I am not familiar with that food, is it a powdered commercial food? Most commercial foods aren't safe for crabs, they contain additives. Do you feed organic fresh foods? Do you provide adequate protein and have a valcium source available at all times?

Deep cleaning isn't necessary, just spot clean and remove poop and bits of rotting food etc.

Sponges are not necessary, and often just harbor bacteria.
"If there are no dogs in Heaven, then when I die I want to go where they went." -Will Rogers

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Re: Lethargic and not eating

Post by Eggster » Thu Jan 10, 2019 3:00 am

You definitely need to pick up Instant Ocean or some other marine salt. I used the petsmart salt water when first started and while it's enough to keep your crabs alive, it's not what they need. I've noticed, I haven't had a single crab death during a molt since I made the switch a few years ago.

I personally doubt the ammonia smell is the cause of Tiny's issue since the other crab is fine. Did you ever figure out the source of the smell that came from the smaller tank/cage?

Yeah, I second the assertion that that food probably isn't safe. You can get dried shrimp, dried blood worms, mealworms, etc from petsmart for pretty cheap; just look in the reptile,turtle,and fish sections. There's a "reptile veggie blend" that's good, it contains: dehydrated vegetables, dried mealworms, and dried crickets. It's safe and my crabs certainly go for it.

All in all, try the marine salt, new foods and avoid opening the tank lid often. Hopefully it'll work out for ya.

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