Why does Phosphates keep depleting?

RaymondL · Mar 22, 2024

Hi everyone,

The phosphates in my tank consistently drops to 0.01ppm, and I dose to bring it up to 0.03 and then a day or two later it drops again. There's no skimmer on or anything out of the ordinary in the filtration system, so I'm wondering what's happening here. Nitrates tend to drop as well.

Welcome to ideas as I'm still finding my way around all this.

Thanks

crazyfishmom · Mar 22, 2024

RaymondL said:
Hi everyone,

The phosphates in my tank consistently drops to 0.01ppm, and I dose to bring it up to 0.03 and then a day or two later it drops again. There's no skimmer on or anything out of the ordinary in the filtration system, so I'm wondering what's happening here. Nitrates tend to drop as well.

Welcome to ideas as I'm still finding my way around all this.

Thanks

Hi! How old is your tank? Was it started with dry or live rock? How was it cycled? How much bioload do you have between coral and fish? I think these answers will help us try to help. Also, posting all of your tank parameters can at times give us clues too.

Hallowhead · Mar 22, 2024

Adding to crazyfishmom

Do you have corals ? Coraline ?

Randy Holmes-Farley · Mar 22, 2024

Sounds like demand is just higher than the food and dosing additions if nitrate is dropping as well. I'd either feed more or dose both as needed.

Hallowhead · Mar 22, 2024

Randy Holmes-Farley said:
Sounds like demand is just higher than the food and dosing additions if nitrate is dropping as well. I'd either feed more or dose both as needed.

My only question, that I myself face, is could he be feeding an algae breakout ?

RaymondL · Mar 22, 2024

Hallowhead said:
Adding to crazyfishmom

Do you have corals ? Coraline ?

Tank is 1.5 months old and is a mixture of soft and LPS corals and 2 clownfish. Salinity is stable at 1.0260, dkH: 9.1, Ca: 450ppm, K: 1450ppm, Nitrates: 5ppm, Phosphates: 0.01ppm [at the moment], there's no coralline algae at the moment. I used dry rock to start - took 1 month to cycle prior.

Randy Holmes-Farley · Mar 22, 2024

Hallowhead said:
My only question, that I myself face, is could he be feeding an algae breakout ?

You mean a future risk, or a current consumer?

doubleshot00 · Mar 22, 2024

RaymondL said:
Tank is 1.5 months old and is a mixture of soft and LPS corals and 2 clownfish. Salinity is stable at 1.0260, dkH: 9.1, Ca: 450ppm, K: 1450ppm, Nitrates: 5ppm, Phosphates: 0.01ppm [at the moment], there's no coralline algae at the moment. I used dry rock to start - took 1 month to cycle prior.

Sounds like a typical new tank. Keep dosing (dose more) or wait it out. Keep your testing up.

Do you have a roller mat?

Hallowhead · Mar 22, 2024

Randy Holmes-Farley said:
You mean a future risk, or a current consumer?

Feeding a potential future risk. I find my nutrients deplete quick right before an algae breakout

crazyfishmom · Mar 22, 2024

RaymondL said:
Tank is 1.5 months old and is a mixture of soft and LPS corals and 2 clownfish. Salinity is stable at 1.0260, dkH: 9.1, Ca: 450ppm, K: 1450ppm, Nitrates: 5ppm, Phosphates: 0.01ppm [at the moment], there's no coralline algae at the moment. I used dry rock to start - took 1 month to cycle

In a tank this young and started with dry rock there’s the potential that the rock will absorb some phosphate for a while. I honestly think that raising to 0.03 is actually taking a very conservative approach because you’re within the sensitivity range of the Hannah instrument so you may be adding enough to get to 0.03 but maybe not. While a conservative approach is usually what I advocate for, I might consider shooting for 0.06-0.07 which is still a pretty reasonable number for phosphate and look at the trends then. May be more manageable to maintain the levels there.