I've had my 140g tank set up for 2 yrs. now and have had poor results with plants no matter what I do. Barely can keep crypts, swords, sag alive let alone grow & reproduce. Tank lighting is 4-33" T-5ho 6,500K bulbs so that should be plenty for crypts at least. Two months ago I got the dry ferts. & started EI dosing on a daily basis. That has had no noticeable effect. Years ago when I had 1200 g of water set up, I had crypts growing & reproducing in all my tanks using the old T-8 grow bulbs & never used any ferts. As a last resort; I'm going to change over to Safe-t-sorb. All things being equal; can I expect to see a dramatic improvement with my plants? Is Tractor Supply the only source for STS?