30 Gallon Tank red clawed crab/ calcium and iodine chemicals

HI a few weeks ago I bought two red clawed crabs, one died so I bought four more and my dad bought eco calcium and eco iodine. he only qestion I have is if iodine is needed for the crabs and if that the bottle says marine that it is for only saltwater. Mine is a fw 30 gallon with mollies, guppys, neon, plecos, catfish, loaches and crabs. Also what the first signs of molting and what can I do or add to make this process easier and less stressful/dangerous to the crab



Thanks,
Ryan

 

I have fiddler crabs in a brackish tank with crushed coral and coral sand substrate. I don't add iodine, but I do mix sea salt into the water when doing water changes. My crabs have been fine through 6 or 7 molts so they must be getting what they need from the sea salt, crushed coral, and food.

Providing the proper environment is one of the most important aspects of keeping any living creature. Most crabs are not fully aquatic or truly freshwater, so when possible they should have access to the surface and be kept in brackish water. The brackish water may not be possible in a community tank, but make sure they have some way to climb up out of the water. Also, without enough hiding places in a community tank the crabs may be vulnerable to attack from other crabs or fish following a molt. Providing plenty of cover will help reduce stress and increase the potential for a successful molt.

 

I have a turtle dock for the crabs (where they spend most of their time) and have had 1 sucsessful molt and 1 unsucessful molt, the unsucessful one started in the evening and the plecos moved him and probably stressed him out the sucsessful one happened during the day, with both of these I didnt add anything and the sucessful one actually grew her other claw back!!I will probably start adding small supplements of calcuI'm though which should help the crabs, snails, and I'm buying ghost shrimp soon. And do I need to buy some special food for the crabs because so far ive never seen them at the bottom of the tank

 

I feed them Crab & Lobster Bites which are sinking pellets. I usually sprinkle them on the "beach" and in the shallow water part of the tank. They seem to enjoy beach combing for food . Mine also pick algae off the filter and rocks when it starts to accumulate, though that is more of a supplemental snack.

If you don't have any other source of minerals like crushed coral then adding calcium might help them out. I haven't ever used supplements though so I couldn't say for sure how well they work.

 

I add aquarium salt (not marine) to the tank so the fish cld have better slime coats, I dnt think this helps the crabs but I figured it cldnt hurt them, I also added calcium and yesterday I had another sucessful molt, also thses guys are true escape artist ive had three escape (always found them) but now ive got it completely blocked off. So far so good with my 30 gallon community

 

Red clawed crabs are definitely not compatible with almost any fish species, your tank is especially unsuitable.

These crabs are brackish water, and the water needs a rather high salt content. I'm sure that this will kill the neons, catfish, loach and pleco, and be very damaging to the guppies. When the crabs grow large enough, they will attempt to eat smaller fish like the guppies.

Also, red-clawed crabs need a constant access to land, and a half-land half-water tank would be better. That surely won't work with your fish.

Obviously, it would be much nicer to get a 10 gallon tank that is devoted just to these fascinating crustaceans - 2/3 filled with water, with a large chuck of driftwood that protrudes out of the surface. It has to be brackish, and then separate the crabs from the community tank of fish.