Phosphate increase after scrubber 0 nitrate

[stevec]

Hi

I have been running an ATS for a couple of weeks now. It is a little underpowered but I am working on that. I have noticed that although my nitrate is not measurable I.e. 0 on my test kit, the phosphate has been increasing. The algae on the rock is diminishing, the strands are lighter in colour and weaker and a lot less glass cleaning required. I have read a few threads on this, done the usual google mission.

Is nitrate a limiting factor in the absorption of phosphate by the scrubber. Could phosphate be being pulled out of detritus in the rock and gravel?

Cheers
Steve

[SantaMonica]

Welcome from the UK.

No I don't think you are ever limited by N or P in an aquarium scrubber. Some scrubbers have zero N, some have zero P, some have zero both, and they all grow great. If some N or P still shows, stronger scrubbing usually takes care of it.

Yours sounds like P has been coming out of the rocks for a while and is almost done. All the rock algae should then come off.

[stevec]

Thanks, good to know I don't need to dose nitrate.

[SantaMonica]

Just remember, that if your scrubber is growing, it's getting the nutrients it needs. More/stronger scrubbing, of course, would remove more and bring the testable-phosphate down further.