A clam should be fine, they need very little elbow room, but they don't tolerate being picked on.
General rule is that clams under 3" need to filter feed, while larger ones are fine with photosynthesis alone.
They require intense lighting usually, similar to SPS
. But don't burn their mantles.
They don't like a sterile tank, a bit of organic material seems to benefit them.
Don't move them around after they attach, it can kill them. If you want to try it in a few areas, sit him on a small saucer with gravel in it. Once you find a location he likes you can remove the saucer and let him root himself.
Be sure to not expose him to air. If you do, he needs to be inverted and shook to insure there are no bubbles trapped in him.
Start with an easy one, not that bright blue maxima at the LFS
Generally low flow as they don't like their mantles messed with.