Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
You can start with the Seachem product line, available in small bottles, and each bottle has a different fertilizer so you can customize the blend. It sounds like a lot, but just buy it once, while you are figuring out your tank. I think they call all their fertilizers Flourish.
Flourish Excel (a source of carbon)
Flourish Comprehensive (trace minerals)
Flourish Iron (Comprehensive has iron, but some people think it is not enough)
Start with the lowest dose on the labels.
N, P, K and Excel on one day (like M-W-Fr)
Comprehensive, Iron and Excel the other day. (Tu-Th-Sat)
Water change on Sun. Dose GH booster (Seachem Equilibrium) only if needed.
If you find the plants seem to need something different alter ONE material at a time. Then monitor conditions for a week or two and see if that fixes it.
Once you get the right light, fertilizer and carbon squared away there are cheaper ways to buy the fertilizer, though it takes a bit of mixing. You can buy the dry forms of the active ingredients.