Derasa gaping

[aerius007]

Here is the situation. I have two clams, a crocea and a derasa. I have the crocea on the rock in the upper 1/3 of the tank, the derasa on the sand bed. The crocea is fine, had for around 4-5 months. I have had the derasa for around 2 months.

When I bought the derasa it was in great shape and looked very healthy, it had been kept under T5's previously, in a shorter tank though. I have 8 54w over a 120g, it was under 2 54 in a 33g. I did add a phosban with gfo about two weeks ago and currently run carbon in a Magnum 350. The calcium and alk did drop recently, nothing drastic just no bionic for a few days, I took a few days to get the numbers back up but did so gradually.

My skimmer also did go crazy for a couple of days after I used some harveys putty to stick down some frags (thats the reason I have the magnum with carbon running right now). The mantle also looks as if its losing color. Is it just too far from the lights or a combination of things?

What action should I take at this point, give it to a friend and see if it improves?

Alk now 10.3, calc 415. was 7.8 and 375 a few days ago, dosing with bionic and have been doing regular water changes.

 

[a4twenty]

lighting is fine, assuming they are all not actinic and the reflectors aren't covered in salt creep.

gaping, when talking about clams is different than other inverts, please post a pic.

i would guess that the big jump in Alk has caused the problem, though posting a picture would be best, we can tell so much from a pic.