Clam Question

[qn5]

Do you think I can keep a clam under 48watts of T5 and 195 watts of PC in 20 long?

 

[scsinet]

I think that will be okay, particularly for a less finicky species such as T. derasa.
It's possible that T. maxima, T. crocea, or T. squamosa might need more intensity, but you are at 10+ wpg and not a lot of depth, so you might be okay with anything.

 

[sleeri]

A Squamosa would probably do fine. They've got a brown mantle, which means they require less light. The only draw back is that they grow real fast.
I've got a thriving Squamosa at the bottom of my 55G (216 T5 watts). I've had it for over a year now.