Clams are best under metal halides. However, you have a very good T5 system so I would still keep them high up, but they should be ok under your lighting.
Derasa, Squamosa & Hippo clams are lower light requiring & your best choices. Maximas & Croceas are very high light clams so not so suited for that lighting system.
Is it a Tek or some other system with individual reflectors?
Mik, not to be rude but you just started & have not yet had any clams. It is probably better to wait till you have some hands-on experience before you give advice on a topic that might lead someone to make a decision that they will later regret. When people ask if things will do well, they are needing information about long term thriving, not a few weeks or a few months of surviving. We were all newbies at one time, and I think its great that you're so enthusiastic about this new hobby. But it's best if you slow down & enjoy the process. After you've tried out a few more things in this hobby, then you can post about your own experiences & speak with knowledge gained from what you've done. I know at 14 the future seems so far away, but with this hobby, time will pass quickly & soon you'll no longer be a newbie but one of the old-timers
Peace.
Anthony