I should mention the details.
The substrate is Caribsea Ecocomplete. I have substrate cabling if not for anything but just uniform heating.
The lights are an Arcadia 4x54W T5 fixture with T5 Grolux tubes, and a cheapo Catalina 4x55W PC fixture with GE 9325K tubes. They both have the crappy flat square type reflector, so light delivery is not as good as it should be. With one ban of PCs turned off, it's been 3.1W/gal up til now, but I've just decided to switch them all on and make it 4.15W/gal. See what happens.
50% water change every 8 days along with ferts, which are: JBL Ferropol (containing no NO3 or PO4), Flourish Excel, Flourish Iron, with NO3 and PO4 dosed separately to Tom Barr's 7:1 ratio.
As soon as I can find a plant wavelength LED light fixture, I'll get one, and not just because they'll be better for plant growth than what I have now, but also a lot of the fish like the Cardinals would prefer much softer lighting.