P04 test kit madness

Centerline · Apr 9, 2017

I just completed testing for P04 with the following results.

Salifert - 0.01
Red sea Pro - 0.09
Hanna ULR - .18
Hanna LR .15

All I can say about these kits is, well, what the heck. I had started using the Salifert kits about six weeks ago because they were fast and easy. Over the last week I noticed my sps looking a tad pale, tested P04 and decided it was time to dose a little NeoPhos. After having a hard time getting to .03, last night I used twice what I was using and thought it best to test aging this evening before double dosing again. Salifert reported .01 and that just didn't seem possible so out came the Hanna ULR kit. It reporting 0.18 certainty didn't seem possible and so I cross checked it with the Hanna LR coming in at .15. At that point I pulled out the RedSea Pro kit for a confusing and maddening .09. Sigh....

Which kit would you trust? I'm inclined to trust the Hanna kits. And yes, none of the kits are near their expiration dates.

Kershaw · Apr 9, 2017

I would re test each one several time in a row to make sure your numbers are consistent. To help remove human error. Then next step would be to send a sample to Triton test the sample then let them test and which ever is closer would be the test I would use if phosphate is that important to you

JimWelsh · Apr 9, 2017

I really like and trust the Nyos Phosphate Reefer test kit.

ijv · Apr 9, 2017

if i want to know figures then a lab.report is more efficient
most affordable test kits will give me a reference as in too much/little ......works fine for me

Centerline · Apr 9, 2017

Kershaw said:
I would re test each one several time in a row to make sure your numbers are consistent. To help remove human error. Then next step would be to send a sample to Triton test the sample then let them test and which ever is closer would be the test I would use if phosphate is that important to you

Ya, I am considering a triton test. Just did one about 6 weeks ago and don't really want to spend the cash but it should create things up a bit.

Kershaw · Apr 9, 2017

How dose you tank look? Do you have algae ? If you don't have an algae problem then pick the test you like most. So .18 could be fine for you tank if you don't have nussance algae.

saltyfilmfolks · Apr 9, 2017

Centerline said:
I just completed testing for P04 with the following results.

Salifert - 0.01
Red sea Pro - 0.09
Hanna ULR - .18
Hanna LR .15

.

lol. Guess I can just trust an api and save the money for more corals.

ijv · Apr 9, 2017

tad pale does not have to be po4......
my former sps tank was nitrate 24 /po4 0.18

Centerline · Apr 9, 2017

ijv said:
tad pale does not have to be po4......
my former sps tank was nitrate 24 /po4 0.18

Tad pale before I started dosing.

Centerline · Apr 9, 2017

Kershaw said:
How dose you tank look? Do you have algae ? If you don't have an algae problem then pick the test you like most. So .18 could be fine for you tank if you don't have nussance algae.

I run a ULN system and from time to time it requires the addition of P04 and N03. Thus I have a ULR and LR Hanna. My experience has been that at near 0 P04 corals stop growing and can start bleaching with high alk and light levels and no nutrient. I dose to keep the levels at .02-.04.

Scorpius · Apr 9, 2017

I don't trust any test kit for any reason. Today was a prime example. I use Salifert for calcium and I got a 405. I tested again 415 and the third time a 420.

A few days ago it was 425 so the 420 the third time today was most accurate. I also tested for Strontium today and that read around 420 as well. I normally don't have any issue with the Salifert Calcium. I didn't do the test differently today so I haven't a clue what happened.

Randy Holmes-Farley · Apr 10, 2017

Scorpius said:
I don't trust any test kit for any reason. Today was a prime example. I use Salifert for calcium and I got a 405. I tested again 415 and the third time a 420.

A few days ago it was 425 so the 420 the third time today was most accurate. I also tested for Strontium today and that read around 420 as well. I normally don't have any issue with the Salifert Calcium. I didn't do the test differently today so I haven't a clue what happened.

IMO, all the values from 405-425 are within the expected error of a hobby kit, and fortunately, it is accurate enough for our needs.

Did you really mean the strontium came out at 420 ppm? That obviously isn't correct unless you massively overdosed strontium. Personally, I wouldn't bother measuring it.

Scorpius · Apr 10, 2017

Randy Holmes-Farley said:
IMO, all the values from 405-425 are within the expected error of a hobby kit, and fortunately, it is accurate enough for our needs.

Did you really mean the strontium came out at 420 ppm? That obviously isn't correct unless you massively overdosed strontium. Personally, I wouldn't bother measuring it.

The Salifert Strontium test kits also tests for calcium as part of it's testing process.