Name: Tridacna crocea|
Crocea prefer to be put on live rock. Maxima prefer the sand bed. Crocea don't get very large, max about 15 cm or so, but Maxima can get huge. I have kept Crocea under power compacts high up in the tank, in the top few cm under the brightest light and it did just fine. Smaller (less than 3 cm) are MUCH harder to keep, as they need more plankton than a sub-adult or adult clam. Spend the extra and get something 5 cm or more in length, have power compacts and live rock and place this clam very high up in the tank, and it will be just fine.
If you are going to keep these clams, do your research on it's tank mates. Just about all shrimps and crabs (exception, skunk cleaners and scarlet hermits, my observations) will love to nip the mantle. Many, many fish that won't touch a coral WILL try to nip the mantle of these clams. Best kept with plankton or algae eaters in a reef tank. Fish like Royal Grammas and other pseudos, basslets, firefish, blennie, and hawks were just fine. Any angel, and any butterfly will quickly consume this wonderful animal, as will arrow crabs, large hermits, and most starfish.
High lighting, preferably metal halide, and good calcium and alkinity levels are a must for this species, as well as with most giant clams.
I have enjoyed great sucess with this species over the past three years. I keep my crocea in a 45 L nanocube under a 24 W power compact. I have kept it at various height levels in the tank, but this particular clam seems to prefer to be placed directly on the sand bed. There are seven blue-legged hermits, a black capped basslet, and a pygmy angelfish, all of which have lived in harmony over the past three years.