Thanks J I put in a few iron tabs in the substrate, which is a knockoff Fluorite-type product made for ponds, but other than that only dose a water-column iron supplement infrequently (weekly or bi-weekly). 4-5” of substrate. Pressurized CO2 injection.
Lights are DIY… six 3-foot T8 bulbs, 4 of which are 3000k and two 10000k (hard to find 5000k, my preference, in a 36” bulb), and two 4-foot T8’s, one 5000k and one 3000k. So, 230 watts, but T8’s are stronger than T12’s, so I believe the effective wattage is more like 350 or so, which I guess translates into 2 to 3 watts per gallon or so, say 2.5 watts/gal.