View Full Version : Crab Conditions

07-06-2011, 12:01 AM
I recently converted my 29 gallon tank to a crab setup. I lowered the water level to the halfway mark and put lots of driftwood in so the crabs had above water access. Currently there is just a single Red Chilli Crab in the tank with a few random other fish (a pleco, two cories, and a handful of tiger barbs). I have another Red Chilli and two Blue Moon Crabs on order. I was wondering if anyone knows the optimal pH level for the crabs? I haven't been able to find much online and what I have found stated a higher pH. I did a test of my water today and it is actually fairly acidic.

07-06-2011, 03:02 AM
ive never kept crabs before but that tank sounds like a disaster in the making. the crabs will/might go after the fish. two corys are not enough for them to school and be happy. im not sure what a handful of tigerbarbs is (number-wise) but they also like to be in big schools and can be very nippy towards other fish. if the pleco is a common it will get too large for the tank, and even smaller species will really stress the bioload of the tank.

my recommendation would be to get a new tank to keep the crabs/fish in and have the crab tank be species only. it will save you the headache

07-06-2011, 04:05 AM
I don't know too much about this specific type of crab, but as far as I know, there are no truly freshwater crabs. Meaning, you cannot keep them in fresh water indefinitely. Eventually, they will become sick and die. What they need is brackish water, slightly salty. And generally hard water. Crabs also require calcium for their shells, which is a component of many marine salts which you can use to mix up your brackish water. The ideal salt content may vary for different species so I am not sure what would be best for your crab. I keep my fiddlers between 1.005 and 1.010 specific gravity, but I could raise it a little bit and they would still be fine.

And as far as keeping the other fish in there. Most people who keep crabs keep them with few to no other fish. I keep a couple minnows in my tank and they DO get eaten. Also, if you did keep fish in there you would have to go with fish that do well in brackish conditions. I would still not recommend it because crabs will nip at fish and kill them if they can. It is nice to have some fish in there, as long as you are okay with them being eating occasionally. I would definitely move the fish you have into a different tank. Then you can optimize that one for your crabs. You could even build a beach on one side of the tank. But if you don't want to do that, the driftwood will be fine. Also, I would check on the water temperature your crab needs. They generally need warmer water.

07-06-2011, 03:42 PM
The remaining fish are leftovers from the previous setup. I've had a crayfish before and at another point a different crab as well. I'm fully aware that the crab may go after the other fish. I even returned a few fish to the store in the process of converting the tank. If the crab goes after the remaining fish I'm not really concerned about it. I'm more concerned about setting up the tank properly for the crab(s).

Thanks for the info SLeen. The water in my tank is fairly soft currently. Any suggestions? I had someone recommend tap water for my water changes in order to get harder water but I have concerns about using straight tap water.

07-09-2011, 05:01 PM
the water should become harder with the addition of salt. You can also increase the hardness by adding limestone. But I dont think that should be necessary if you have enough salt in the water.