Hanna Phosphate and Phosphorus checker accuracy?

[Camaro Show Corals]

I’ve always had good readings with mine

 

[YumaMan]

I just found this thread after I googled "How to check the accuracy of a Hanna Ultra Low Phosphate Checker". I have given up using my brand new Hanna checker out of frustration, and here's why: my first test of water from my DT yielded 0.04 ppm P. Every subsequent test from the same DT has yielded 0.00 ppm P. When I test my other DT, Hanna yields 0.00 ppm P. So I decided to add a drop or two of some FastMStart to the Hanna test vial water (FastMStart contains P as well as other elements) and the Hanna test reads 0.00 ppm P. So I added lots and lots more drops of the FastMStart to the test vial water just to make sure that the cosmos is still intact, and the result was unchanged, o.oo ppm P. Then I put the Brand New Green Hanna ULR Phosphate Checker back in its pretty new box. It now adorns a spot under my utility sink. Maybe somebody in this forum can convince me that this instrument was worth $42 plus the cost of 40 reagent refills. The accuracy on my device is probably +/- one zillion ppm.

 

[Randy Holmes-Farley]

So I've had the Hanna phosphate checker for a few months now which has always read zero. Not convinced with the accuracy I just got the Hanna ULR phosphorus checker to compare, but it again reads zero. My last Trition ICP test showed P at 24 ug/l and PO4 at .07 mg/l.

I have a good amount of algea growing on glass that needs cleaned every 2-3 days so I'm thinking the Trition results make more sense. Anyone have any faith in the Hanna checker reading?

FWIW, the Hanna is only testing a subset of what Triton tests for detection of P, so one cannot assume that the Hanna must be wrong if it disagrees with the Triton test, even if the Triton test is perfect.

For example, Hanna detects no organic forms of phosphate (DNA, RNA, phospholipids, etc.).

And, of course, as folks have noted, both methods have uncertainly levels associated with them that make number not need to agree perfectly.

 

[Randy Holmes-Farley]

I just found this thread after I googled "How to check the accuracy of a Hanna Ultra Low Phosphate Checker". I have given up using my brand new Hanna checker out of frustration, and here's why: my first test of water from my DT yielded 0.04 ppm P. Every subsequent test from the same DT has yielded 0.00 ppm P. When I test my other DT, Hanna yields 0.00 ppm P. So I decided to add a drop or two of some FastMStart to the Hanna test vial water (FastMStart contains P as well as other elements) and the Hanna test reads 0.00 ppm P. So I added lots and lots more drops of the FastMStart to the test vial water just to make sure that the cosmos is still intact, and the result was unchanged, o.oo ppm P. Then I put the Brand New Green Hanna ULR Phosphate Checker back in its pretty new box. It now adorns a spot under my utility sink. Maybe somebody in this forum can convince me that this instrument was worth $42 plus the cost of 40 reagent refills. The accuracy on my device is probably +/- one zillion ppm.

What makes you think quickstart contains any specific amount of phosphate?

If it is just residual in the water used to grow the bacteria that the product contains, it might be highly variable batch to batch, and might even be none detectable with a Hanna.

 

[YumaMan]

Well, I do trust your answer although I have only limited knowledge of organic chemistry. My main problem is that my 120 gal reef has a bad outbreak of green hair algae and bryopsis (I think that's what its called), plus Bubble algae. I want to combat these through wholesale hand removal of the algae, water changes, reduction of organic feed to corals, increased skimming, and lowering the nitrates and phosphates. This sounds logical to me but the algae just keep a-coming despite my NO4 and P readings being at 0. If the tests would yield some numbers, I could then take either more remedial action or encouragement that my labors will eventually pay off. As it stands it leaves me dumbfounded (not difficult to do). I will eventually be able to control the algae with Yellow Eye Kole tangs and a Lawnmower Blenny, but I must first set up my quarantine tanks and then count 75 days. Meanwhile, my tank could feed a small manatee!

 

[YumaMan]

I also have added GFO in a sock in the sump for a week. The algae mocks this intervention as well and charges forward.

 

[Randy Holmes-Farley]

FWIW, bryopsis and bubble algae (valonia) are two types that can grow OK at the levels of nutrients needed for corals, so just reducing nutrients is not usually going to work for them without hurting other organisms.

 

[Tritie]

Will the Hanna phos checker detect P2O5 in AquaVitro's supplement?

 

[Randy Holmes-Farley]

Will the Hanna phos checker detect P2O5 in AquaVitro's supplement?

There is NO reefing supplement that contains P2O5. The labeling of fertilizers is a regulatory convention for indicating the amount of P in them by P2O5 equivalents, not an indication of what form is actually in it. P2O5 is not stable in water.

Are you using Aquavitro Activate (intended for planted tanks)?.

That product is potassium phosphate. It is certainly detected by the Hanna.

 

[Tritie]

There is NO reefing supplement that contains P2O5. The labeling of fertilizers is a regulatory convention for indicating the amount of P in them by P2O5 equivalents, not an indication of what form is actually in it. P2O5 is not stable in water.

Are you using Aquavitro Activate (intended for planted tanks)?.

That product is potassium phosphate. It is certainly detected by the Hanna.

Hi,

Yes. That is what I am using. I'm having low phos and extreme nitrate increases every week (3-5 ppms per day). The 2 local lfs near me just had the AquaVitro. I do not have any corals in my 65 gallon system just a small hermit and a few fish (two clowns and a chromis). I'm doing 50% water changes weekly. I have put enough Aqua Vitro in the tank that I should get a reading of 0.15ppm. I get nothing. Even when I tried a different box of Hanna phos reagents, I get nothing. I'm testing about 15-30 min after adding it. I just purchased a Salifert test kit and it's the same thing. I had intended to purchase the Hanna LR this past weekend, but grabbed the incorrect one (LR), which I already have. Even if I put half tank water and half AquaVitro, I cannot detect it with the test kits (2 min mixing plus 3 minute count down). Although at one point this weekend, I accidentally left a vial of 100% tank water (no addional phos supplement) that read 0.00 in the Hanna after the 2 minutes of mixing and 3 minute count down and when I discovered it the next morning, it was dark blue.

 

[Randy Holmes-Farley]

Hi,

Yes. That is what I am using. I'm having low phos and extreme nitrate increases every week (3-5 ppms per day). The 2 local lfs near me just had the AquaVitro. I do not have any corals in my 65 gallon system just a small hermit and a few fish (two clowns and a chromis). I'm doing 50% water changes weekly. I have put enough Aqua Vitro in the tank that I should get a reading of 0.15ppm. I get nothing. Even when I tried a different box of Hanna phos reagents, I get nothing. I'm testing about 15-30 min after adding it. I just purchased a Salifert test kit and it's the same thing. I had intended to purchase the Hanna LR this past weekend, but grabbed the incorrect one (LR), which I already have. Even if I put half tank water and half AquaVitro, I cannot detect it with the test kits (2 min mixing plus 3 minute count down). Although at one point this weekend, I accidentally left a vial of 100% tank water (no addional phos supplement) that read 0.00 in the Hanna after the 2 minutes of mixing and 3 minute count down and when I discovered it the next morning, it was dark blue.

In a low phosphate situation, you may have to dose huge amounts of phosphate to get a reading because much of it may be binding to rock and sand surfaces. That doesn't explain the out of tank test though. Maybe the product has been used, refilled with tap water, and returned to your lfs. lol

If you run out of that product, or want to switch now, switch to food grade sodium phosphate from amazon. Much cheaper and it has a purity rating the Aquavitro product lacks.