Seriously what phosphate test is accurate?

[DereksReef77]

I don't seem to trust any phosphate test kits for the home use. I have a hanna phosphate checker I use every day by the way. Today I used the same solution and tested it 5 or 6 times.

I got:
.10
.08
.06
.06
.03
.08

Then I used a salifert phosphate kit and it was pretty much undetectable. What to believe? All of my zoas are shrinking on me. I've lowered light but don't know what the problem is.

Alk 8.3
Cal 425
Mag 1380
Nitrate 5
Salinity 1.0245
Ph 8.2
Temp 77.2

Please help!!
All test kits are salifert

 

[BoneXriffic]

Id say even with the fluctuations it would appear tou know your lower than .1 phos. Ive reached .4 before l. My zoas survived it fine. I wouldnt thing its a phos issure with the zoas

 

[DereksReef77]

Yes I can agree with the statement that I am at .1 or less but the salifert says it is 0-.03 there was next to zero blue color so which is accurate because if it is truly zero then that would probably be why im having issues with my zoas. No?

 

[RMS18]

My hanna will show .01-.03 off if I found multiple tests

 

[Salty1962]

Following on best test kit.

 

[slicko]

the hanna phosphate eggs have a accuracy of +- 0.04 so all those results seem fine to me. imo phophate eggs are the most accurate and easy to use.

 

[wcharon]

I have read of several people using the ELOS Prof. kit. I haven't used it yet so i can not guarantee that it is accurate. Will be getting one next week to corroborate.

 

[Anthony kolodziej]

http://www.googleadservices.com/pag...ow-range-photometer?format=visible&source=ads

these are pretty good

 

[Kungpaoshizi]

The Hanna 736 is the most accurate on the market atm iirc..
They're +/- error rate is parts per billion, not parts per million like other tests..

 

[slicko]

http://www.googleadservices.com/pagead/aclk?sa=L&ai=CHOuDqt4vV6GiIYPl7gbGuaP4Aq6P_s5Ekqr_yPUBlrrfrvgBCAQQBCgFYMnG2438pKgToAHGxu3LA8gBB6oEJ0_QmiK1UROzDo-nzXHXRy2A3X6sD6YXqh6gCy2ozeyh1iQUn0LKvcAFBYgGAaAGJoAHormSNJAHA6gHpr4b2AcB4BLk4JP5_vyeki0&ohost=www.google.com&cid=CAASJORoZL52BPpndmRf6fbiohZmcradosZCoaMd2O_CEfE4suiFaw&sig=AOD64_1VRf99gj5-krUVXBtwuwjvQE5Zxg&ctype=5&clui=7&q=&ved=0ahUKEwi_gvT64svMAhUDRhQKHcBHDj4QvhcIMQ&adurl=http://labequipmentdepot.com/product/milwaukee-instruments-mi412-phosphate-low-range-photometer?format=visible&source=ads

these are pretty good

no more accurate than hanna egg 717

" ±0.04 mg/l @1.00 mg/l "

 

[Sabellafella]

The hannah box works good. The elos professional i found to be the best But its very expensive

 

[DereksReef77]

I forgot to mention that I hooked up a diy algae scrubber about a month ago and it must finally be broken in and is now removing more nutrients than I've been putting in. Duhh my bad I think that is my problem. But as far as the hanna egg I'm not trusting it. I believe the salifert is more accurate as it is showing very little color change in the test to support my theory that I haven't been feeding enough. I'll keep posted my findings but I will try the elos I tried to get one tonight from brs but they were sold out of it.

 

[Randy Holmes-Farley]

I don't seem to trust any phosphate test kits for the home use. I have a hanna phosphate checker I use every day by the way. Today I used the same solution and tested it 5 or 6 times.

I got:
.10
.08
.06
.06
.03
.08

Assuming it is the 713, that is exactly in line with their claimed specification of +/- 0.04 ppm.

 

[JimWelsh]

Elos Pro for the win!

 

[DereksReef77]

Thank you sir!!

 

[shred5]

Hobby grade kits are not accurate you have to look at the more expensive lab grade kits like hach.
D-D phosphate kits are accurate too and are based of Merck test kits at least they used to be.

lamotte test kits would most likely be the best hobby test kit.

Really no phospahte test kits is much good because they only test for orthophosphate.

 

[jason2459]

Hobby grade kits are not accurate you have to look at the more expensive lab grade kits like hach.
D-D phosphate kits are accurate too and are based of Merck test kits at least they used to be.

lamotte test kits would most likely be the best hobby test kit.

Really no phospahte test kits is much good because they only test for orthophosphate.

Lamotte PO4 kit is lacking IMO

Best hobby grade kit to me would be from Hach.

From there a tie between Elos Pro and the hanna 736. Pros and cons to me in below PO4 kit review.

Some more common test kit reviews I've done and recommend.

A Nitrate Test kit shootout betweenNYOS, Salifert, RedSea Pro, and API
https://www.reef2reef.com/threads/nitrate-test-kit-shoot-out-nyos-salifert-redsea-api.221323/

A PO4 test kit shootout between Nyos, Elos Pro, Salifert, Hanna Checkers x2, and Seachem.
https://www.reef2reef.com/threads/po...s-pro-salifert-hanna-checkers-seachem.222628/

Me vs. Triton
https://www.reef2reef.com/threads/hobbyist-vs-triton-testing.221320/

All the Above along with AWT vs. Triton which also includes another follow up Triton test
https://www.reef2reef.com/threads/tr...ts-api-salifert-elos-redsea-hanna-etc.222909/

The final Big 3 Shootout Alk, Ca, Mg: RedSea, Nyos, Elos, Salifert, API, Hanna, Triton, AWT
https://www.reef2reef.com/threads/bi...os-elos-salifert-api-hanna-triton-awt.234660/

 

[Cory]

Ive come to the conclusion that the best phosphate test isnt a test, but watching how quickly algae grow.

Second conclusion, spend money on gfo, not po4 test kits.

 

[jason2459]

I don't remember the last time I spent any money on GFO.

 

[shred5]

In order to test a test kit you need a solution that has a known value. You can not test them against each other for accuracy really.
A couple of years ago I tested a bunch of test kits. I have always tested my new kit compared to my last. If they were way different I tested with a 3rd or 4 th test kits,
I got a couple of bad salifert that were so off someone could nuke a tank.

You can not even get good test solutions anymore. I just ordered from brs calibration fluid for my refractometer and it read higher than the two older bottles I had. I ordered a pinpoint just to make sure it wasnt something with the old kits and it also read lower than my new one. BRS never got back to me on the issue.

My point is the only real way to test a kit is with a reference solution.