How to control phosphates???

as stated above in all posts, #1 u have to maximize export and minimize import ie feeding, skimming ( wet imo) find a tlf gfo reactor and strip the water. last but no least ro/di water. if your getting it from a store I would invest in a TDS meter, esp if you make ur own water. test ur lfs store water and if its high in tds move on and find another source of water.
I had to find out the hard way in the begining. had a store selling me water i figured was good till i got a lil more educated in water chem. come to find out it was almost tap water (gross over statement but is was really bad water) and i constantly had algae issues.
and dont get talked into bandaides... they dont fix the problem you have to get to the root of the issues. the prob is most LFS will sell you band aides instead of educating you and helping you get to the root of the problem, so beware. Ive been there and being an lfs emp, i do my best to help others avoid wat i had to endure.
you could also do wat the call "cooking your rock" in a bad tank your LR has the ability to absorb po4 and continue to leach it in to the water... ie if you only grow HA on ur rock work then that shows you where the fuel is coming from for it. thats where fluidized medai comes in handy, but be careful as stated above you can take out to much, is normal and natural to have some po4 present.