I've gone through Florida Aqua Farms for my phyto cultures and equipment before, very good results. The culturing itself is rather simple. I also prefer to get a few different strains and then when dosing my tank, mix em up a phyto cocktail. They sell the algae fertilizer, which is what I use, but you can make the same stuff, plenty of DIY recipes floating around the web. Alternatively, you can start a culture from using products like DT's live phytoplankton but it's kinda a crapshoot as to what strain you'll end up with. The nanno is very opportunisitic but that's no guarantee. Last time i spoke to meleve on the subject of phyto, he said he was still using miracle grow fertilizer with great results (this was several years back) but I read enough potentially bad things about it, I chose to play it safer and get algae specific stuff through FAF.
for the actual strains, I prefered to use Chlorella, Tetraselmis, and T. iso, no particular reason other than variety. Tetra is a larger motile phyto while the others are bit smaller and non motile. (actually i'd have to double check, pretty sure t iso is nonmotile but the chlorella may be, or i'm thinking nanno... FAF site will say lol)
