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Cable 08-09-2011 01:45 PM

Red Handed Crabs upside down
I got some Red Handed Crabs on Sunday and after much reading through various forums I'm not 100% as to what is wrong.

One of the four crabs is upside down and has been all morning. I went to "fish" it out but it took a snap at my net showing it wasn't dead.

I've read that it could be having a bad molt, the water is too cold and the nitrates may be high.
The water is at 28 Celsius which is what I've always had my tropical tanks as as suggested by the store I purchase from and the water tests are fine.

I've also heard that the crabs like to be out of the water. I even asked about this "whether or not they'll try to escape" and was told they won't. - Unusual as I've always had good things to say about that store.

I've got a log going diagonally across my tank, the top of it is slightly out of the water. Would you suggest creating a platform of some sort for the crabs to sit on out of the water that they can climb the log to access?

I've kept tropical fish for over two years now and I thought I'd experiment with these Red Handed Crabs.

One thing that may be of importance is that there are four small green barbs in the tank with the crabs. There was a fifth but it was ill when I bought it and has since died.

Could this crab be going through a bad molt? Thankfully it's at the front of the tank so if needed I can upload a photo.
Also, should I make a shelf for them to sit on outside of the water?

Thank you

Andarial 08-09-2011 01:59 PM

I don't know it they would escape or not, I know my red claw crabs try to, but they are two different kinds of crabs from what I understand. I do know that most crabs are intolerant to high nitrites, and tend to die from poisoning if it is too high. They will freeze up and sometimes flip over until they are put in fresh water without high nitrites if you catch it quick enough you can save them. Most fresh water crabs do need to get to air, I just wouldn't trust them about getting out. So I would find a way to put screening over your filter hole and heater hole.

Hope this helped a bit ^^

Cable 08-09-2011 02:05 PM

Thank you,
My aquarium is pretty robust, the lid shuts and there is no way for anything to get out as the wires are fed through slots.

I think I need to do another test on the nitrates etc. What's confusing is that one of the crabs (the largest in the tank) seems very lively. It's crawling up the log and jumping off before repeating this process for hours on end. The other three seem very quiet and they are considerably smaller than this one. It's almost twice the size of the smallest crab.

Now the four green barbs are fighting each other. I've never had these problems before and I've kept barbs for months before hand. Its 20:05 right now, I'm going to have to make some phone calls and visits to the fish store tomorrow I think.

ladayen 08-09-2011 02:38 PM

Check all your parameters, ammonia, nitrite, nitrate, PH. What kind of filter do you have and is there an air pump in that tank?

I'm not certain about your green barbs, but other barbs like to be kept in groups of 6-8+, maybe want to try adding a couple more in there.

Another thing is it could be your lighting. My danios start nipping at each other if the light is left on too long, or especially if I turn it on later for some reason.

I'm not terribly familiar with crabs, but it sounds like a possibility it's a bad molt. Have to check your paramters to rule those getting to high. Is it possible a barb has decided to flip it over?

Cable 08-09-2011 02:44 PM

I'm not sure. Its missing a leg and it seems that the shell is coming off, but I've seen them flip themselves over and self right just as easily.

The guy at the store refused me more than five barbs so they can settle in. I'll have to get some more to see if that helps once I've checked the chemicals.

I have a 20(ish)cm air Stone which is on reasonably strong and a filter that I cannot remember the name of. I'm out at the moment and will have to check later.

Thank you.
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ladayen 08-09-2011 02:49 PM

If it's missing a leg something has probably attacked it. Possibly done more damage then you can see. Maybe a barb, or even another crab. What else is in the tank and how big is it?

Cable 08-09-2011 02:54 PM

three more crabs, one considerably larger than the others and just four small Green told that when they shed they can easily loose a leg and will regrow it later.
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redchigh 08-09-2011 03:02 PM

Red claw crabs need-

Lots of hiding places so they don't get eaten during a molt. Preferably allow them to dig their own burrows in sand.
Iodine supplementation- through food, or a reef iodine supplement dosed at half strength. (helps with molting)
Lots of land area- They are mostly terrestrial, and rarely submerge themselves in nature.
Brackish water- Ocean salt, and a hydrometer... Salinity, at minimum, 1.005.
Access to fresh water for drinking occasionally.
A tight-fitting lid- they are little escape artists and surprisingly strong.
A heater- 72-80 degrees F

(BTW, assuming red claw crabs- Sesarma bidens),%20R5.jpg

Cable 08-09-2011 05:22 PM

my tank is a taller tank so its going to be tricky to make hiding spots but I'll certainly rearrange it with a couple of caves etc

Thank you for the information that is extremely helpful!
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Andarial 08-09-2011 08:32 PM

Oooo I thought they were completely different crabs, because I looked up red handed crabs and got something different than red claw... Yeah I agree with what Redchigh says.

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