Can't seem to get my phosphates in check...

[homer1475]

I’m currently running rowaphos in my mini as well, still can’t seem to get it lower than .05. My main issue is I can’t seem to get rid of the diatoms. Everything else looks great.

Have a picture? Might not be diatoms, might be cyano.

If it is diatoms, they feed of silica which will not be taken up by phosphate removing media.

 

[ReefGeezer]

So if your phosphates are .11, the rock also has phosphate bound to it at .11. Every time you lower the phosphate concentration of the water below that level, the rock will leach some phosphate until a new, very slightly less equilibrium level is reached. Even without additional phosphate input, it takes time and many GFO changes until the equilibrium level of the water and the rock are lowered to the level you want.