Thanks Tom for the info on CO2 and PO4. I don't do CO2 injection in my tank (haven't gotten the $$$ for it yet) So I don't get to play around with the possibilities of CO2 and how it affects nutrient uptake. I guess in that way I'm somehwat stunted in my knowledge of nutrient and algae control. I'm still experimenting with my tank to figure out what things work for me and I'm trying to learn all I can. Here's a question for you, is it possible that when I notice an algae bloom in my tank, that it isn't solely phosphate but other nutrients that are in the water & ferts?

You're right about that and I get the Phosphate=algae thing from what I've read but also because when I add the fertilizers into the tank water or kick up the substrate, I get small algae blooms. However the compound in my fertilizers (which are terrestrial) is not PO4 (Phosphate) but P2O5 (Phosphorus pentoxide - a dessicant from what I've read). Perhaps that has something to do with the occurrence of algae when I add it to the tank. Would you agree?

I'm experimenting with terrestrial fertilizers because I want to find the best way to fertilize my tank without spending tons of money on pre-made aquatic fertilizers that I feel are overpriced. Unfortunately to say I still haven't gotten a lot of chance to experiment with PMDD and making my own ferts.