Nitrate and phosphates dosing

SoGaReefer · Apr 5, 2026

I recently had a 25 gallon tank with quite a bit of Rock which only lasted about four or five months before I realized it was time to upgrade. Right before upgrading I added a good bit of Rock to the tank and when I made the switch to the new tank I added even more dry Rock I am assuming my rocks are just absorbing all my nitrates and phosphates as they are both staying about zero. Well they are zero not about. New tank has been up an going for about a month with fish and corals and all. Should I be dosing nitrates and Phosphates to keep them visible and help speed up absorbtion so they will stay stabled

Stevorino · Apr 5, 2026

I'd just feed a lot heavier until you get the phos over .05 and nitrates over 5 consistently.

My understanding is that rock doesn't absorb Nitrates the way you are suspecting. Phosphates can be absorbed but they shouldn't be to the point where its taking you to zero. Being @ non-detectable with good test kits is begging for a Dino/Turf Algae breakout.

Dosing Nitrates & Phosphates is something I personally wouldn't consider until well after a year. JMO but dosing nutrients are something only to be done when running a mature tank when coral demand is beyond what is reasonable to feed.

SoGaReefer · Apr 5, 2026

Stevorino said:
I'd just feed a lot heavier until you get the phos over .05 and nitrates over 5 consistently.

My understanding is that rock doesn't absorb Nitrates the way you are suspecting. Phosphates can be absorbed but they shouldn't be to the point where its taking you to zero. Being @ non-detectable with good test kits is begging for a Dino/Turf Algae breakout.

Dosing Nitrates & Phosphates is something I personally wouldn't consider until well after a year. JMO but dosing nutrients are something only to be done when running a mature tank when coral demand is beyond what is reasonable to feed.

Thanks for the answer. All the reading I've done says they can and will absorb for a while behind they were dry rocks.