Hannah accuracy: Phosphate ULR vs Phosphorus ULR

[Miami Reef]

What is more accurate, the phosphate ULR or the Phosphorus ULR Hannah checker?

They seem to both have +/- 5% of readings, but one of the reading will be in PPB (the phosphorous) while the phosphate will be in PPM.

 

[ColoredRock]

What is more accurate, the phosphate ULR or the Phosphorus ULR Hannah checker?

They seem to both have +/- 5% of readings, but one of the reading will be in PPB (the phosphorous) while the phosphate will be in PPM.

what are you looking for and why? I personally have looked at numbers as indicators. Just curious.

 

[Miami Reef]

@ColoredRock

I’ve had the phosphorus checker for about 2 years but I’m getting annoyed by needing to convert my results all the time.

I want to know if switching to the ULR Phosphate will be a significant downgrade.

 

[Timfish]

Ditto. Just FYI but Hanna Phosphorus ULR is testing for phosphate then converting it to it's equivelant phosphorus amount but is not testing for organic phosphorus so organic phosphporus in not included in the number.

 

[Miami Reef]

Ditto. Just FYI but Hanna Phosphorus ULR is testing for phosphate then converting it to it's equivelant phosphorus amount but is not testing for organic phosphorus so organic phosphporus in not included in the number.

I actually watched a video where someone speculated that the Phosphorus ULR and the Phosphate ULR have the same exact reagents that are just labeled differently. Not sure if that’s true.

 

[Timfish]

It is, both tests are only testing for phosphate (aka PO4). Since the "ULR phosphorus" test kit is giving results in PPB it's "more sensitive". Since there's solid research showing we shouldn't let PO4 drop below .03 mg/l and we can't test for particulate or organic phosphorus I don't see a need to test phosphate at PPB sensitivity.

Fig 4 from this paper

 

[CoralB]

Hanna Phosphate ULR is the one I use and gets you to the .05 - 1. Specs required . Just don’t fall asleep during the 3 min count down as it’s easy to lose the reading in you don’t set a time as it doesn’t store your results . That’s my only issue about it . Hanna could have spent another dollar to include a storage for at least the last numbers taken

 

[ColoredRock]

Tim that made my head hurt :)

 

[ColoredRock]

reading the abstract was actually very informative tho.

 

[Randy Holmes-Farley Verified Community Expert]

The specifications from Hanna claim the phosphorus checker is more accurate than the phosphate checker for measuring phosphate.

 

[nereefpat]

I’ve had the phosphorus checker for about 2 years but I’m getting annoyed by needing to convert my results all the time.

You get annoyed easily :p
You just multiply by 3 and move the decimal.

 

[Miami Reef]

You get annoyed easily :p
You just multiply by 3 and move the decimal.

Oh, I had to google a chart from Hannah’s website each time.

 

[defasum]

The Apex controller calculates for you when you select the Phosphorus ULR option at input. Have it set by default and just plug in my PPB number

 

[nereefpat]

Oh, I had to google a chart from Hannah’s website each time.

To get ppm phosphate
Take ppb phosphorous x 3.066 and divide by 1000.

So 7 ppb phosphorous is about 0.02 ppm phosphate, for example.

 

[LeftyReefer]

To get ppm phosphate
Take ppb phosphorous x 3.066 and divide by 1000.

So 7 ppb phosphorous is about 0.02 ppm phosphate, for example.

Right, both seem plenty accurate enough for our use.... so if you want readings in ppb, get the 736.
If you want readings in ppm, get the 774.

@ColoredRock

I’ve had the phosphorus checker for about 2 years but I’m getting annoyed by needing to convert my results all the time.

I want to know if switching to the ULR Phosphate will be a significant downgrade.

No. Why would it be a downgrade? If you are wanting the results in ppm and If it will save you the trouble of doing the conversions each time, then it would be an upgrade from what you have now, right?

If you are annoyed at doing the conversion now, go ahead and upgrade to the 774.

option #1 use 736, get 7 back, pull out chart, do the conversion, get back .02 ppm. done.
option #2 use 774, get back .02 ppm. done.

I fail to see how that would be a downgrade. PPM is plenty accurate enough. I've never once felt the need to have results in ppb vs the ppm I get with my #744. If someone gave me a #736, and took away my #744. I would definitely see it as a downgrade though.

 

[PatW]

There is a rule of thumb in low nutrient systems that you want .03 ppm phosphate or lower. For the ULS phophorus, that is just a reading of “10” and I suppose you want at least .01 ppm which would be a reading of 3. So even for the most sensitive test out there, you are wanting to stay right at the low end of its functional range. If I get a reading of “0”, I add some phosphate. I want some phosphate but not much. My SPS do fine and oddly enough, my LPS are happy too and they are supposed to want higher nutrient levels.

 

[Miami Reef]

There is a rule of thumb in low nutrient systems that you want .03 ppm phosphate or lower. For the ULS phophorus, that is just a reading of “10” and I suppose you want at least .01 ppm which would be a reading of 3. So even for the most sensitive test out there, you are wanting to stay right at the low end of its functional range. If I get a reading of “0”, I add some phosphate. I want some phosphate but not much. My SPS do fine and oddly enough, my LPS are happy too and they are supposed to want higher nutrient levels.

I don’t even want ultra low nutrients because I get Dinos when phosphates drop that low. It’s not fair though.

It still boggles my mind how some people can maintain ultra low nutrients without Dino’s. I really like the coloration of ULN acros.

 

[jim_fitz]

To get ppm phosphate
Take ppb phosphorous x 3.066 and divide by 1000.

So 7 ppb phosphorous is about 0.02 ppm phosphate, for example.

i do phoshate removal for one of the largest utility companies in the UK and as such i dont understand how Hanna make such recommendations, in that Total P (all phosphorous) is not in a direct relationship with ortho phosphate

and i cant find a recommendation for values of Total P in a reef tank so ive given uo measuring it

And Id also love to know where the original piece of work is that showed that reef tanks should ideally be 0.03

so to side track a bit but this subject is my passion

 

[nereefpat]

i do phoshate removal for one of the largest utility companies in the UK and as such i dont understand how Hanna make such recommendations, in that Total P (all phosphorous) is not in a direct relationship with ortho phosphate

I'm not sure if you meant to quote me or not.

Phosphorous in seawater and our tanks is primarily phosphate, either organic or inorganic (ortho). See if this RHF article is helpful to you: https://www.reef2reef.com/ams/phosphate-in-the-reef-aquarium.9/

and i cant find a recommendation for values of Total P in a reef tank so ive given uo measuring it

And Id also love to know where the original piece of work is that showed that reef tanks should ideally be 0.03

I see recommended values between 0.01 ppm phosphate to 0.1 ppm. That seems reasonable. The ocean is closer to 0.01. It's easy enough to measure with a ULR Hanna kit. Most (all?) hobby kits aren't very useful below 0.1.

 

[CoralB]

I'm not sure if you meant to quote me or not.

Phosphorous in seawater and our tanks is primarily phosphate, either organic or inorganic (ortho). See if this RHF article is helpful to you: https://www.reef2reef.com/ams/phosphate-in-the-reef-aquarium.9/

I see recommended values between 0.01 ppm phosphate to 0.1 ppm. That seems reasonable. The ocean is closer to 0.01. It's easy enough to measure with a ULR Hanna kit. Most (all?) hobby kits aren't very useful below 0.1.

Yes but in the reef tank no matter how big or small running phosphates at 0.01 is hard to maintain . To easy for it to zero out