Phosphates won’t go down.

[Jordanwilsher]

Hi, writing this for my cousin, his tank had a bad out break of Algea, did his test had high phosphates and nitrates. Started doing more water changes and doing Nopox. Algea went, did all my test again, nitrates are close to 0 now, but the phosphate reading has never changed around 1 ppm. Any one can help explain why

 

[flagg37]

I’ve read that nopox needs no3 to reduce po4. I’ve never used it so I don’t know. If this is the case you should try something like gfo or phosguard that focuses on removing po4.