phosphate ??

[delamfe]

I'm using NO3Po4X and it works really good when you find the exact balance. My nitrates are 0 and phosphate 0.02, maybe too low because some corals areturning brown.

 

[justhaag]

before i switched out my filtration i would put a phosphate sponge into the sump and that would drop mine down to 0 everytime

 

[Nanook]

I shoot for .02-.05 with my Hanna meter, once I get to .07, I know my GFO is starting to deplete and needs replacement.