Phosphates rising after changing HC GFO

[Randy Holmes-Farley Verified Community Expert]

Thought if I removed the algae that the phosphates went with it. Guess what u mean in a nutshell is the phosphates have less surface area to bond too. Just added more gfo we'll see what happens. I dont wanna strip my water to zero phosphates

That phosphate already in the algae is exported, but the ongoing consumption of phosphate by the algae is reduced. From a soluble phosphate perspective being minimized, you want to have as much algae in the tank as possible. lol

Just think of the extreme case: remove all the algae. Then there will no longer be any consumption of phosphate by it, and phosphate will rise.

 

[Rubberfrog]

Thought if I removed the algae that the phosphates went with it. Guess what u mean in a nutshell is the phosphates have less surface area to bond too. Just added more gfo we'll see what happens. I dont wanna strip my water to zero phosphates

The algae was consuming the gfo

 

[Randy Holmes-Farley Verified Community Expert]

The algae was consuming the gfo

Are you being sarcastic? I cannot tell.

Algae will take up soluble iron, but not enough to impact the export of phosphate by GFO.

 

[FreeEnergyReefer]

Update. When I added the gfo it knocked out half the algae in my fuge. I now know is the reason why phosphates went up in the water column. With half the algae gone it took 2 n a half cups of gfo in a reactor to knock the phosphates down to .05, riding steady there. Once I replace the algae this minor issue seems to be under control. Thanks reef peoples

 

[GSnake]

I experienced the same rise in phosphate after gfo. I was puzzled, but this just happened to me. I'm going to continue with weekly gfo changes for now

 

[Randy Holmes-Farley Verified Community Expert]

I experienced the same rise in phosphate after gfo. I was puzzled, but this just happened to me. I'm going to continue with weekly gfo changes for now

FWIW, I expect it is coincidence/test error. :)