Derasa Placement

[The Shark]

After a ton of research and shopping...I just bought my first Derasa Clam yesterday. He is about 3", with a great brownish-gold pattern, and appears to be very healthy.

My LFS told me that since he was smaller, I should put him on my rocks first, and as he grows, he will bump himself down to the sand. Everything that I have read says that Derasa clams like to be on a sandy bottom with a rock under them to attach to. (I have 4 48" VHO's, so he may need to be a little higher to take in the lesser light)

I have good placement spots in both the rocks and sand...which way do I go?

 

[chris&barb]

Derasa's will do fine either on the sand or the rocks. in the wild they can be found in both places. what we really need to know is how deep is your tank and how high are your lights?

 

[The Shark]

The tank is 24" deep, and the lights are about 5 inches above the top of the tank...so I figure he would be better to sit high on the rocks to get the most light.

 

[chris&barb]

24" is kinda of pushing it, although i do think VHO's are nice. Derasas are a little more tolerant of lower light levels but i think it would be happier closer to the light

 

[morgan]

when ever im diving i have never seen clams on sand maybe im not looking hard enough but they are always on a rock they are very hard to look at 2 cause they always close so fast

 

[chris&barb]

when ever im diving i have never seen clams on sand maybe im not looking hard enough but they are always on a rock they are very hard to look at 2 cause they always close so fast

thanks for your observation Morgan.

ive tried to make that point a few times.all the clams can be found up on the reef. some can be found on hard calcium carbonate substrates(not really sand or reef). the only time you will find clams in sand, they will be in very sheltered areas where the sand dosent blow around. no clam could last long on a dynamic sand bed. the whole "this clam is a rock clam and this one is a sand clam" is unfounded.

if you take photos when you dive, i would love to see as many clam shots as you can bare to post

 

[lovesalt]

Good luck with your derasa! I bought mine at 3 inches, 3 years ago and now it is 8 1/2 inches!!!

 

[redrooster]

so I should move my clams up a bit out of my sand bad? I have a deresa and a squamosa. Both seem to be doing OK. I would need to move them up slowly as I am running 500+ watts of MH on a 75G but maybe up just a little onto the lower rock structure?

On a side note on a piece of LR I got about 6 months ago a "clamlike" stucture starting "pumping" yesterday. It looks like a clam, but is attached to the rock with the hinge facing up from the rock. It has no mantle as far as I can tell. It was open quite a bit yesterday and started opening and closing wildly. This thing has never moved in the previous six months in the tank. I moved the rock to a higher flow area recently and am assuming that is what spurred its activity. Is this an oyster? Any guesses. I will try to get a pic, but I am sure it will not help as it really looks like it is part of the rock.

 

[chris&barb]

so I should move my clams up a bit out of my sand bad? I have a deresa and a squamosa. Both seem to be doing OK. I would need to move them up slowly as I am running 500+ watts of MH on a 75G but maybe up just a little onto the lower rock structure?

there's no need to move the clam. it seems like its been doing fine where it is so i would leave it there.

the placement of clams really depends on your lighting and space. if your lighting can reach the clam on the bottom of the tank its fine to leave it there.

i just think the classification of clams as "rock clams " and " sand clams" is silly because in reality the majority (large majority) of them in the wild are found on the reef/rocks. just because a few of the species can occasionally be found on the sand shouldn't warrant these species as having a preference for it.