gfo or bio pellets

[christopherjudd]

is there a general preference between gfo and bio pellets with a sps tank?

when using either one, does it visually change (like in color etc) when exhausted?

thanks!

 

[Eastone]

Biopellets will disappear, they get consumed, but GFO doesn't change in colour afaik.

 

[downbeach]

GFO works more specifically on PO4, while BP's will take up some PO4, the bacteria that are consuming it are taking up more NO3. As mentioned the BP's will ultimately be consumed by bacteria, and need to be added to, the GFO will become exhausted as it has absorbed as much of the PO4 as it can, and will need to be replaced with fresh, or regenerated GFO periodically.