Carbon dosing question

[USMA36]

I started dosing nopox about 1 month ago to bring my nitrates down from 60. So far my nitrates have dropped to about 12 Using the recommended dose of 3ml per 25 gallons in my 100 gallon total volume system. My phosphate has dropped to 0 using the Hanna checker. It used to run .05 or so while running gfo. I stopped gfo about 2 weeks ago. Should I add neophos or just reduce the nopox dose? I already feed fairly heavy and I have a heavy bio load.

 

[Quietman]

hmm...I ended being nitrate limited (meaning at 0 nitrate I had .05-.10 phosphates) which I believe is more common. Either way, I think I'd let it go another week or two before dosing phosphates. If you were 0/0 I would recommend dosing, but with nitrates at 12, I'd just let it stable out a bit longer and see where it ends up. You may end up dosing phosphates or feeding bit heavier. Once thing I noticed about NoPox is that it takes a few weeks to run stable (due to what I believe is fluctuations in bacteria population and nutrients). Also, PO4 will bind with carbonate in rock so give it some time as well for the PO4 to equalize and disassociate from the rock.

 

[ZoWhat]

DIY nopox

650ml Vinegar 5%
350ml Vodka 80proof

 

[Dan_P]

I started dosing nopox about 1 month ago to bring my nitrates down from 60. So far my nitrates have dropped to about 12 Using the recommended dose of 3ml per 25 gallons in my 100 gallon total volume system. My phosphate has dropped to 0 using the Hanna checker. It used to run .05 or so while running gfo. I stopped gfo about 2 weeks ago. Should I add neophos or just reduce the nopox dose? I already feed fairly heavy and I have a heavy bio load.

If you are growing coral, 0 ppm might not be the best for them. Also, at very low phosphate, nitrate consumption could stall during carbon dosing.

I am surprised no one has warned you about dinoflagellates being more likely to appear at 0 PO4.

You might consider adding PO4 if you want the carbon dosing to bring down nitrates further, but I would up the frequency of PO4 testing to avoid surprises.

 

[YankeeTankee]

I'd verify all of this with a second test, which you may or may not already done. Once verified in the short term I'd consider both but definitely would dose phosphate, Dan is right, the last thing you want is Dinos and there is plenty evidence that bottoming out PO4 will do that. There's plenty of inorganic phosphate for dosing out there. Good luck

 

[Uncle99]

It would be unusual to get a zero reading of phosphate in ant tank which is fed.
The margin of error on the Hanna is 0.04, so even a zero is likely higher, and that reading is just fine.
Continue to lower nitrate from 16 to 2-5 with NoPox, then reduce 1 ml per week until the nitrate starts to increase, then up the dose 1 ml.
I have kept my nitrate at 5ppm for years now.
I have not had any problems with phosphate in the 0.05 to .15 range.
Continue to seek stable numbers, rather than minor differences in tests, which reaps the greatest benefits.