your tank is much like mine! How many curviceps do you have? There are currently 2 in my tank and I believe I may have a pair. Anyway I have been using some pond tabs that I found at petsmart. they are much higher than everyone recommends but so far so good. My sword plants were not doing well, yellow leaves then holes in the leaves. these tabs gave more iron than the flouris and were half the price. I've been using them about a month with no problems.