Most human-readable phosphate test kit?

[Bob 1000]

Photometer..

 

[HighlandReefer]

2thdeekay,

Did you compare the kits to each other or a known standard?

 

[2thdeekay]

2thdeekay,

Did you compare the kits to each other or a known standard?

Both. I tested my tanks water first (one sps reef, the other is fish only) with all the above kits, and Hanna low range. Then made serial dilutions of 1M Na2HPO4 down to 1.0, 0.10, 0.03 & 0.01 ppm PO4 to test also.

Merck seems to read 0.03, but the color difference is pretty slight. For the most part, Hanna was ok with the 0.03 as well, but varied by +/- 0.01. There were a few high readings with the 0.1 & 0.03 reference sol'ns. Changing to a new cuvette seemed to fix the issue.

Neither were useful with the 0.01 ppm reference.

 

[Frogmanx82]

I just got the elos test. The values for matching colors are 0 0.01, 0.05, 0.10, 0.25, 0.50, 0.75, and 1.0. The color differences are fairly easy to match and you only need two drops of each reagent. A pretty nice wet test.

This seems to be the most focused test on low level phosphates.

 

[Av8bluewater]

I doubt the margin of error is +- .04 on the Hanna... That may be the disclaimer(for cya) but I think it's more accurate than that.

 

[Billybeau1]

The problem with the API and the reason I do not like it is it is difficult to determine between .25 and zero ppm. This kit is not a good choice for PO₄ for saltwater.

I have not tested the Merck or Tunze so I can not comment on those.

The Salifert, from my testing, does a pretty good job as long as you are not color blind.

I do not like the color chart of the Elos. I find the colors too difficult to distinguish.

When I run out of projects, I may tackle this one next.

 

[HighlandReefer]

Both. I tested my tanks water first (one sps reef, the other is fish only) with all the above kits, and Hanna low range. Then made serial dilutions of 1M Na2HPO4 down to 1.0, 0.10, 0.03 & 0.01 ppm PO4 to test also.

Merck seems to read 0.03, but the color difference is pretty slight. For the most part, Hanna was ok with the 0.03 as well, but varied by +/- 0.01. There were a few high readings with the 0.1 & 0.03 reference sol'ns. Changing to a new cuvette seemed to fix the issue.

Neither were useful with the 0.01 ppm reference.

Thanks.

 

[2thdeekay]

Thanks.

You're welcome!

Has anyone compared the Martini with the Hanna or DDMerck?
http://www.aquabuys.com/page/aqb/PROD/mi_phos_photo

 

[Bob 1000]

I compared my martini against salifert, and 2 hannas.. No comparison.. I can press the button immediately after pouring in the powder and stirring it up and get a reading in5 secends that is accurate.. Hands down the best out there next to the guy in the lab with the $10,ooo piece of equipment,,lol..

 

[Billybeau1]

That is quite impressive. Quite expensive, but impressive.

If it does what it says it does, I could see a few reefers investing 160 bucks on this.

I'll sic Boomer on this one. He will get to the bottom of this.

 

[2thdeekay]

http://www.milwaukeeinst.com/index_sz_news_products.htm

 

[bertoni]

I doubt the margin of error is +- .04 on the Hanna... That may be the disclaimer(for cya) but I think it's more accurate than that.

People have called Hanna and asked, and they won't say it's more accurate than that. It might be, but I don't see any reason to believe it.

 

[HighlandReefer]

I am curious as to how the chemists are able to detect phosphate readings below 0.001 (as in Randy's article where the found readings around 0.005). I guess expensive equipment.

Nothing available within financial reach of us poor hobbyists?

 

[Av8bluewater]

People have called Hanna and asked, and they won't say it's more accurate than that. It might be, but I don't see any reason to believe it.

I have a reason.. numerous tests comparisons against other test kits.

 

[2thdeekay]

Hmmm. That Martini PO4 meter seems to have similar specs to the Hanna low range. Martini docs lists accuracy @ ±0.04 mg/l @1.00 mg/l, with resolution of 0.01 ppm.

Certainly ±0.04 ppm accuracy @ ~0.03 ppm would not be useful at all, but Hanna specifies only "±0.04 ppm". I wonder if there's info they've omitted.

 

[bertoni]

Any data on the accuracy of photometers would be interesting.

 

[Frogmanx82]

Can the hanna photometer be used for reading other tests? Seems like a lot of money just to run phosphate.

 

[tmz]

Nope, just low range inorganic phoshate. They do make other meters for other pruposes.

 

[Billybeau1]

pruposes

No spell check Tom ? :lol:

 

[tmz]

havn't foundthe speil chek sinc the upgrude.