Hi guys, back in 2001 I have bought myself a 7 gallon tank with water a stick to go out of the water, gravel some filtration and basiacaly freshwater. Then I went and bought 2 fiddler crabs and 2 red claw crabs, the all lived untill all of them died with in a month. Only one red claw crab lived 7 months and died. Then I lost my interest and gave up. Now I want to sart over but I want to know all of the facts that will make my crabs live their full life which is about 2.5 years I belive. Please can you answer these questions!

(1) Is 7-10 gallon tank enough for anout 7 crabs?

(2) What pH does water need to be? Is 7.0 pH would be fine?

(3) What kind of salt and how much will I need to keep the water brakish with stability?

(4) What tempature will I need? Is 77-80 F okay?

(5) WHAT FILTRATION WILL I NEED?

(6) How much water will I need? Is 5-10 inches above would be fine?

(7) Will the Red Claw and Fiddler Crabs can live together?

Please if you can answer this!

(1) Is 7-10 gallon tank enough for anout 7 crabs

Nope! Far too small, I would go for a 3ft tank for one male red claw/fiddler and two to three females. You also need plenty of hiding places and caves to avoid fighting. 10G is not enough to provide enough hiding places in and out of the water for each crab.
2ft would be the minimum unless you want to keep only one crab, but they do better and are more active during the day if there are more than one.

With a tank that small, when each crab moults, it will almost certainly be attacked and eaten by the others.

(2) What pH does water need to be? Is 7.0 pH would be fine?

7.0 is fine, 7.5 is better, with moderate to hard water. Give them cuttlefish bones as an extra source of calcium.

(3) What kind of salt and how much will I need to keep the water brakish with stability?

I kept red claws in fully fresh water for overthree years, though a little salt (1 Tbsp per gallon) may help prevent bacterial diseases. Fiddlers can be kept in fresh water too, but I haven't kept any myself, so I would go with 1 tbsp of aquarium salt per gallon for both.

(4) What tempature will I need? Is 77-80 F okay?

Red claws and fiddlers do best between 22 and 25C

(5) WHAT FILTRATION WILL I NEED?

You must have a cycled filter before adding crabs.
They need excellent water, no ammonia or nitrite, and low nitrate (below 25 ppm. if possible) A small sponge filter should be ok, such as the ones used in breeding tanks, crabs can be messy, but if they are allowed out of water, may keep their dirt above water level.

(6) How much water will I need? Is 5-10 inches above would be fine?

5-10 inches is great, but they can and will escape given half a chance, block all holes where cables come out, and have ventilation through the top of the hood, where they cant reach freedom!

(7) Will the Red Claw and Fiddler Crabs can live together?

Not recommended, they will fight for territory and the large claw on the fiddler gives them an advantage over the smaller red claw.

Thanks, and one more thing, how often will I need to clean out my aquarium for crabs and will 4 crabs would be fine in a 10 gallon tank with alot of hide outs?

I would change half the water once a week, and clean the filter in old tank water once a month. If you want more than one crab in your 10G, one male and one female of either type is the max I would advise, even if they have plenty of hiding places, they have a large territory and wander about quite abit, so fights are inevitable. Do not put more than one male in a 10G, unless you like crabs with only one leg!

Ken

I don't think a crab could survive with one leg! But um will the fiddler male and a fiddler female ever fight? Or I should just get a male fiddler?

Yes, they will fight a bit, but not as much as two males would. Two females would get along better though, with no male.

They could survive with one leg, if you fed them carefully, once they have at least one clw, they can feed themselves, but a three legged crab is a pityful sight I can tell you!

Ken

Yeah maybe someday I will do that but not now because my hobby right now is football and I don't have time to clean and care for crabs even though I really want them!

By the way do you know about Chesapeake Bay? I heard something abou fiddler crabs over there and they are Uca Pugnax. Do you think if I wore to go there I could catch or see one of those things? Also petco seems to be selling the same kind (Uca Pugnax) and it is the same!. Look


Chesapeke Bay fiddler crab:http://www.chesapeakebay.net/fiddler_crab.htm

Petco version:http://www.petco.com/assets/articles/caresheets/pdf/aqffreshwatercrabs052003.pdf

Looks the same!

I have a 29 gallon tank with 1 RCC in it. How many more do you think I could get?

no more then two crabs/ten gallon is the general rule of thumb.