Help!! Need ideas how to raise PO4

[Ptyochromis]

Cyano IN the sand is normal. It is becoming anoxic which is the point.

 

[biggles]

If a lack of phos really is the issue i'd suggest adding a couple of pieces of BRS dry rock to the sump as i see it listed commonly in threads as a source of phos. I'm not saying low phos is your actual problem btw, just giving you a convenient phos source that should be akin to slow dosing, you could adjust the amount of rock needed via Hanna testing. Good luck mate.

 

[CichlidMan@<3]

I may have missed this but why want phosphate? You should want 0 phosphate and some nitrates. Phosphates inhibit growth and can be a cause of color-loss

 

[Ptyochromis]

Uhhh. It may inhibit calcification but they are both necessary for coral growth. Don't forget that corals have symbiotic algae that need some phosphates and nitrates for good growth.

This is the sort of misinformation that gets spewed arround the hobby along with other bs like 'sps don't need to be fed' etc.

 

[SantaMonica]

If your N and P test kits read "zero", you still have plenty of N and P in the water for the corals.