Vampire Crab Death - tips / advice on keeping them healthy

[osmally2]

Hello all! I'm new to this forum and have come looking on information on keeping vampire crabs. I haven't found too many good sources on the internet and decided to post here. I had one male vampire crab I purchased from a guy who was breeding about 2 months ago. The crab was missing two legs when I put him into my original tank set-up and was told he was about 8 months old (not confirmed). My original set-up was a terrarium with very few plants and a Tupperware filled with water with lots of hiding spots in the water. I kept the water clean and monitored tank humidity frequently. On average, temp was 70F and humidity ranged from 65-80%. I have a heating pad underneath the tank (20"x12"x10"), and lights set on a timer.

He seemed OK, was shy and ate every day or two. The guy who sold him to me recommended feeding bloodworms 3 times per week. I fed him more often and tried to throw in some green vegetables for more nutrients.

I rebuilt the tank 1 week ago with a real water feature. I used clay balls under the soil section, and aquarium rocks and sand on the water side - separated by foam. I installed a canister filter with a foam block, carbon filter, and ceramic blocks. I found him lifeless today crammed in a very tight hiding spot between some rocks and the tank wall this morning - close to the filter inlet.

What went wrong? He never molted and I suspect that maybe the water nitrates built up and poisoned him. Could it have been that he was alone in the tank? I've posted a couple of pictures of my set-ups - any input / advice is appreciated!

-o

 

[Ferrachi]

That's a cool looking set up you have there...

 

[pannaking22]

Welcome to the forum! Sorry you couldn't join under happier terms. I don't know a ton about crabs unfortunately, but you can search for a few threads and maybe those will be able to help? @schmiggle maybe?

 

[schmiggle]

Welcome to the forum! Sorry you couldn't join under happier terms. I don't know a ton about crabs unfortunately, but you can search for a few threads and maybe those will be able to help? @schmiggle maybe?

Lol I've never kept these. I do have a couple ideas, but @osmally2 you should take them with a grain of salt.

Nitrate's not likely to be your issue. The chemicals I'd be afraid of are chlorine and ammonia.

It's probably not chlorine, because that wouldn't really have built up, but if you usually treat your water before changing it and forgot this time that's a possibility. It's also possible that the crab started pooping in the new water feature in a way it hadn't with the old one and the ammonia built up over time. If you didn't inject the filter with denitrifying bacteria then a week isn't enough time to see a change. The other possibility is that, because you had the water section connected to the rest of the tank and at the lowest part of it, the ammonia essentially flowed from everywhere else into your water feature. I think that's more likely, and would better explain the change if it turned out to be full of ammonia. Did you do any kind of water test?

If that turns out to be the culprit, I recommend just buying denitrifying bacteria online and injecting them directly into the filter. Some people have wonky results with them, so I'd get it set up a bit in advance and add ammonia and do water tests once a day to see what happens, but it's the best way to avoid problems. Since there's so much less water in this setup than in a standard fish tank, the concentration of ammonia rises much faster than it would in a normal tank. I don't know how messy vampire crabs are, though.

Other than that, I don't really know. Sounds like this guy was wild caught, so it may have come in with a substantial load of parasites, which probably wouldn't have helped. There's a guy on here who breeds these, I think, so you might be able to find those threads. However, it might be cardisoma, which is obviously less useful to you.

 

[pannaking22]

Lol I've never kept these. I do have a couple ideas, but @osmally2 you should take them with a grain of salt.

Yeah I didn't think you had lol, but coffee hadn't kicked in yet. Mainly tagged you for your chemical expertise and maybe the off chance you'd kept these or knew someone that had.

 

[schmiggle]

I found the thread I was thinking of. Don't think he's active, but DR zuum has bred these.

1st artificial incubation and hatch of Geosesarma Dennerle (purple Vampire Crab)

Recently I ordered some purple vampire crabs hard to come by, lucked out got Gravid females all dead....lol. The imbeciles couldn't even look and see they were carrying eggs smashed the eggs up inside their flaps catching them for packing I am assuming. I inspected the dead females found one who...

arachnoboards.com

He emphasizes three things that hadn't occurred to me: microfauna (I think he uses springtails and small isopods), high pH even in fresh water (7.8-8.0--makes sense, Indonesia is full of karst), and ozone, which you can supply with an ozonizer. He did also emphasize the point about WC specimens being weakened.

 

[Introvertebrate]

I've heard that Vampire Crabs are water feature optional. That would be one way to eliminate a potential culprit.

 

[schmiggle]

I've heard that Vampire Crabs are water feature optional. That would be one way to eliminate a potential culprit.

I strongly doubt that--I'm pretty sure land crabs respire using oxygen dissolved in the thin surface tension layer on their gills, which they would have no way of maintaining without enough water to submerge in.

 

[Introvertebrate]

No offense, but I have more faith in the opinion of the fellow on the frog forum I linked to.