Chris -
What do you have in your tank that you KNOW eats phyto?
How many t5's are we talking here? 2x T5's are not enough light. 10x might be. Placement matters, too.
Most stony corals do not eat phyto. They are carnivorous. And the vast majority of the time, the daily feeding of your fish provides an ample food source for stony corals when complemented with sufficient lighting.