Clam turning upside down?

[darkcirca]

I have a crocea clam which I've had for over a year now in my 90 gallon reef tank. I've never had any problems until this past month.

Originally the clam was at the top of the tank, and it gradually made its way into the sand bed. This past month it has turned itself upside down in the sand bed. I've turned it back over on a few occasions, but it always goes back. It still gets some light and looks healthy, but upside down. I have a maxima at the top of the tank that has been in there even longer and it has no problems.

Any thoughts on why a clam does this? I've got 5x54w T5 lighting (Aquactinics fixture), and all the water parameters have been in check. The maxima is happy as can be, as are all my other corals (and fishies).

Also - it's more on its side, with the mantle (this is the colorful part, if I'm correct) either on the sand almost, or under the rock. It still gets a bit of light due to this.

 

[zcwrx]

my new maxima just started doing this the other day. tagging along for info hopefully. my tank is sps dominant with alot of flow and everyday when i get home the clam is in the corner facing away from the lights.

 

[Zire]

<a href=showthread.php?s=&postid=14873350#post14873350 target=_blank>Originally posted</a> by zcwrx
my new maxima just started doing this the other day. tagging along for info hopefully. my tank is sps dominant with alot of flow and everyday when i get home the clam is in the corner facing away from the lights.

Considering SPS tanks tend to have a great deal of light and that the clam seems to be facing away from the lights, the only thing I can think of is that it's responding to excess light from hiding from it.

 

[zcwrx]

I thought maxima's loved light? It's all the way on the sand.

 

[Zire]

Maximas do like strong lights but if it hasn't been properly light acclimated it won't respond well. Do take my advice with a grain of salt though, I don't pretend to be an expert, that just seems like the most intuitive answer to me.

 

[Eggs]

Did you recently change bulbs?

 

[zcwrx]

nope same bulbs since the tank was set up late last year. This morning it was right side up and has stayed that way all day. I turned down the photoperiod a bit.