High phosphate low nitrate issue

OrcaReef

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My 26 gallon Red Sea reefer is about 6 months old. I’m in a constant battle to keep my nitrates above 0 and my phosphate below 0.1. I dose NeoNitrate daily which keeps it about 4-5ppm but if I stop for a few days it bottoms out. My phosphate stays at 1.3 unless I run 0.5 teaspoons of gfo in a mesh bag for 24 hours which causes it to bottom out, I’ll remove it, the level will spike again and then the dance repeats. Has anyone run into this issue or have ideas on how to keep a steady balance?

Livestock:
- two clowns
- one royal gramma
- one fire fish
- one cleaner shrimp plus cleanup crew
-LPS dominate with some softies

RedSea Hardware:
- nano roller mat
- nano protein skimmer

Feeding:
A mix of pellets and rinsed mysis 5-6 days a week
 

Uncle99

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Yup, the roller mat can easily depress nitrates. It’s constantly pulling stuff from the water allowing little to breakdown.

Phosphate looks fine to me, I never go lower than .1ppm, or corals get a bit unhappy.
 

Reef.

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I’m not convinced with your test results for po4, half a teaspoon of gfo imo is not going to lower a 1.3 po4 to zero…what test kit are you using.
 

CHSUB

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I would suggest you don’t have a nitrogen deficiency and dosing no3 is not necessary. Your only issue is a lack of resolution of your no3 test kit and other nitrogen sources you are not testing. With po4, I started running 15 grams of GFO to keep levels below 0.1 in TWV of 40 gallons, currently at 0.06 however I’m fine if it goes lower still.

I don’t really understand your problem? Except maybe your unacceptability of your hobby test kit readings and your desire for a different reading? Are your corals in poor health?
 

Dom

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My 26 gallon Red Sea reefer is about 6 months old. I’m in a constant battle to keep my nitrates above 0 and my phosphate below 0.1.

Do you run a turf scrubber or refugium?

I recently dealt with a similar issue; zero nitrates while my phosphates sat around .1.

The problem was that I was not harvesting from my scrubber frequently enough. This allowed the growth in the scrubber to gobble up all of the nitrates.
 

Randy Holmes-Farley

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Welcome to Reef2Reef!

It's not super unusual to need to dose N or p or both. It just means you have more uptake than foods are providing. I dose ammonium bicarbonate to keep nitrate from getting too low, and I have dosed sodium phosphate in the past.
 

mook1178

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Your tank is still young and trying to balance out. Don't use GFO if your nitrates are bottoming out. Your phosphates are high because you are nitrogen limited. Dose nitrate to around 10 ppm, your phosphates will decrease due to extra nitrate available in the system. Then get your phosphates to 0.05 or so. You are now phosphate limited in that ratio. Nitrates will not decrease as fast and phosphates will likely level out.
 
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OrcaReef

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Do you run a turf scrubber or refugium?

I recently dealt with a similar issue; zero nitrates while my phosphates sat around .1.

The problem was that I was not harvesting from my scrubber frequently enough. This allowed the growth in the scrubber to gobble up all of the nitrates.
No I’m not but thanks for the input!
 
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OrcaReef

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I would suggest you don’t have a nitrogen deficiency and dosing no3 is not necessary. Your only issue is a lack of resolution of your no3 test kit and other nitrogen sources you are not testing. With po4, I started running 15 grams of GFO to keep levels below 0.1 in TWV of 40 gallons, currently at 0.06 however I’m fine if it goes lower still.

I don’t really understand your problem? Except maybe your unacceptability of your hobby test kit readings and your desire for a different reading? Are your corals in poor health?

I would suggest you don’t have a nitrogen deficiency and dosing no3 is not necessary. Your only issue is a lack of resolution of your no3 test kit and other nitrogen sources you are not testing. With po4, I started running 15 grams of GFO to keep levels below 0.1 in TWV of 40 gallons, currently at 0.06 however I’m fine if it goes lower still.

I don’t really understand your problem? Except maybe your unacceptability of your hobby test kit readings and your desire for a different reading? Are your corals in poor health?
Thanks for the input! I’m using a Hanna high range checker and corals are generally ok except for my Goni that was hanging on by a thread, fully receded with exposed skeleton, but it’s been making a slow recovery since I’ve been working to bring the po4 down
 

Reef.

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For phosphate I’m using the Hannah low range Phosphate checker!

Something doesn’t seem right then as I have just checked on the rowaphos calculator, from 1.3 to a drop to 0.03 the amount recommended is 9 tablespoons and that’s in a more efficient reactor, you say you use half a teaspoon in a bag which is less efficient to get to zero?
 

slingfox

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Do you have a lot of rocks or biomedia in the sump? When I had nitrates bottoming out I removed some of my sump biomedia and dose ammonia to help prevent nitrates from going to zero.
 

mook1178

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Something doesn’t seem right then as I have just checked on the rowaphos calculator, from 1.3 to a drop to 0.03 the amount recommended is 9 tablespoons and that’s in a more efficient reactor, you say you use half a teaspoon in a bag which is less efficient to get to zero?
Probably meant 0.13
 

Reef.

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Probably meant 0.13
Yeah you are probably right…I normally catch that but the op seemed so concerned about high po4 I assumed the 1.3 was correct, if it’s really 0.13 that is nothing to worry about unless it’s causing known issues.
 

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