View Full Version : Derasa clam mantle receding

03/12/2017, 09:13 PM
I recently bought a derasa clam and it was doing well for a while but has looked under the weather lately. It responds to shade sometimes and other times it doesn't but it always closes when I touch it.

I have a 10 gallon tank and have AI Prime as lighting. I started a new schedule on it and I think the clam may not be getting enough light. I'm running my lights at 100% and the clam seems to be reacting better to it.

The first picture is when I got it and the next two were about an hour or two ago. I posted my entire tank (don't mind the coralline algae) for light distance reference and the last picture is the clam after I started blasting the lights. He has expelled waste from his siphon and seems to be feeding. (He closes fast and shoots stuff out and then he opens back up)

Maybe I should run a higher intensity light schedule? Here are my levels:

Calcium 450
Magnesium 1400
Alkalinity 11

03/13/2017, 08:37 PM
The clam is dying and it's too late to save it. Deresa won't do well in a 10 gallon. It needs a well established set up. Light wasn't ur issue. Ur setup is very basic. More sensitive animals won't thrive. U need more rocks and get rid of those hob filter.

03/13/2017, 11:47 PM
So what was the issue do you think? The tank is about a year and a half old and I haven't had issues keeping anything yet. All my water levels checked out before I bought it.

03/18/2017, 04:45 PM
its hard to keep parameters stable in a 10 gallon. derasa grows big and sucks up lots of calcium for growth.

04/01/2017, 02:00 PM
I agree with NYCBOB that a 10 gallon is not stable enough for keeping a clam, especially a Derasa. They suck up so much cal, trace elements and fish waste all day long. However, judging from third photo (from left), I think the clam died from something else, not from luck of nutrients in the 10 gallon. It is strange that the outtake siphone looks healthy but the mantle is already receding badly. I lost my derasa clams (2.5-3") like this in my 400 gallon reef. I really couldn't figure it out. They were just fine for weeks, but suddenly the mantles started receding and next day they were gone. I did so research afterward. Protozoa would cause this type of clam death.