Can high po4 affect alkalinity?

[1979fishgeek]

I’m curious if a tank suffering from high phosphate can interfere with alkalinity dosing or somehow bind the chemical to prevent its absorption in the water?

The tank is a friends and corals look ok (mixed reef including Acropora, Monti and various LPS, softies) there is a algae issue with the usual diatoms and green cyano as you would expect at those levels but they are having a problem increasing the Alk. It’s been steadily dropping and is currently just 67ppm. They been steadily increasing the alkalinity part of the two part dosing (Reef Zlements)they are using but it’s not increasing?


Alk 67 (3.7dkh)
Calcium 564
Magnesium 1400
PH 7.9
Phos 1.7
Nitrate 78
Ammonia and nitrite undetectable

I advised to get on top the excess nutrients (no3 and especially po4) they were dosing nopox and now also Rowaphos. I noted the calcium is high and ph is low (possibly from NoPox) but I’m trying to understand why Alk won’t increase and they are dosing loads 200ml a day in 5000l tank. Is there an unwanted chemical reaction happening here or just not dosing enough?

Thanks - Chemistry was not my best subject!

 

[Fish whistler]

I’m curious if a tank suffering from high phosphate can interfere with alkalinity dosing or somehow bind the chemical to prevent its absorption in the water?

The tank is a friends and corals look ok (mixed reef including Acropora, Monti and various LPS, softies) there is a algae issue with the usual diatoms and green cyano as you would expect at those levels but they are having a problem increasing the Alk. It’s been steadily dropping and is currently just 67ppm. They been steadily increasing the alkalinity part of the two part dosing (Reef Zlements)they are using but it’s not increasing?


Alk 67 (3.7dkh)
Calcium 564
Magnesium 1400
PH 7.9
Phos 1.7
Nitrate 78
Ammonia and nitrite undetectable

I advised to get on top the excess nutrients (no3 and especially po4) they were dosing nopox and now also Rowaphos. I noted the calcium is high and ph is low (possibly from NoPox) but I’m trying to understand why Alk won’t increase and they are dosing loads 200ml a day in 5000l tank. Is there an unwanted chemical reaction happening here or just not dosing enough?

Thanks - Chemistry was not my best subject!

 

[Randy Holmes-Farley Verified Community Expert]

No. Phosphate itself contributes a tiny bit of alkalinity, but that’s the only apparent interaction.

 

[tzabor10]

I’m curious if a tank suffering from high phosphate can interfere with alkalinity dosing or somehow bind the chemical to prevent its absorption in the water?

The tank is a friends and corals look ok (mixed reef including Acropora, Monti and various LPS, softies) there is a algae issue with the usual diatoms and green cyano as you would expect at those levels but they are having a problem increasing the Alk. It’s been steadily dropping and is currently just 67ppm. They been steadily increasing the alkalinity part of the two part dosing (Reef Zlements)they are using but it’s not increasing?


Alk 67 (3.7dkh)
Calcium 564
Magnesium 1400
PH 7.9
Phos 1.7
Nitrate 78
Ammonia and nitrite undetectable

I advised to get on top the excess nutrients (no3 and especially po4) they were dosing nopox and now also Rowaphos. I noted the calcium is high and ph is low (possibly from NoPox) but I’m trying to understand why Alk won’t increase and they are dosing loads 200ml a day in 5000l tank. Is there an unwanted chemical reaction happening here or just not dosing enough?

Thanks - Chemistry was not my best subject!

Those numbers don’t add up.
Ca is sky high
All is not at a range I have ever heard of
Please confirm

 

[Fish whistler]

Cut your feeding waaaaaaaaaaaaay down bud. learned about that 16 + ago. try change socks every 2 days

 

[1979fishgeek]

No. Phosphate itself contributes a tiny bit of alkalinity, but that’s the only apparent interaction.

Thank you. I’m wondering if it’s just an error in the doser then. Perhaps it’s something as simple as it’s not dosing what they think it is? Thanks again Randy, much appreciated.

 

[areefer01]

Cut your feeding waaaaaaaaaaaaay down bud. learned about that 16 + ago. try change socks every 2 days

Do you want to eat every other day or meal?

 

[Big E]

Turn off your calcium dosing till it gets down between 400-450.

Are these Reef Zlements pre mixed? If you are mixing, check to make sure you have the correct solutions balanced.

Check to make sure his alk doser is working correctly and not plugged up.

See if his solutions are being used up equally by looking at the containers visually.

You may want to calibrate the alk doser or try using a different dosing head.