I highly recommend this as a hobbyist's first clam. These clams hardier than other varieties that are available. They prefer to be kept on a sandy substrate, and need strong lighting. I highly recommend T5's or metal halides. I also recommend purchasing a clam that is 3+ inches, since they have a much better survival rate than smaller clams. They are filter feeders, and can help aid in nitrate removal. Derasa's also require calcium levels to be within ideal measures. Also, be cautious when placing in a tank with herbivorous fish (tangs, angels, etc). These fish can sometimes nip at the clam, which can cause undue stress.
The derasa is the least demanding of all tridacna clams. This doesnt mean they r easy. The derasa still needs high lighting such as led, t5 or mh since they do best on substrate. this clam can grow 2-3 inches per year. Mine grew from 3 to 9 inches within 3 years. A tank of at least 6 month old is recommended before adding any tridacna clams.
I'm still a newbie and this was my first attempt at a clam. I added it when my tank was about 9 months old and it has been a wonderful success. I first placed it up on a rock shelf half way up from the bottom of my 125 gallon tank so it would be closer to the lights (I use four T5s and 1 T8 per side). After a couple weeks it moved itself off the rock shelf to the sandy bottom and oriented itself the way it wanted to be. It was about 2.25" when I got it and it has grown about 1.5 inches in the last year.
I think its color and markings are very interesting. Its not been bothered by any of my fish, snails, crabs or shrimp. Its been through many algae blooms and other "bad" parameter issues and has survived nicely. Seems to be one tough clam and if you are considering a clam, I highly recommend it as your 1st one to try.
Facts & Details
A great clam for beginner hobbyists with nice blue edging on the mantle. Aquacultured by ORA