You really should get lights that match the length of the tank.
Do you have the TMC 500 single or double? Based on their site I think you need two doubles and single for a total of 60 watts of LED
light. I'm not sure how much light that really translates to as LED
lighting for aqaria is rather new.
I'll see if I can dig up more information. In the meantime, what type of corals are you thinking of?
What is your filtration system composed of?
What problems are you currently facing?
What livestock do you have in the tank?
What are you water parameters (please post actual numbers for temp, pH, Ammonia, nitrite, nitrate, calcium, alk
, and magnesium and anythign else you can test for.