which test should I rely on for my phosphate reading?

reefmaster70

Valuable Member
View Badges
Joined
Jan 24, 2025
Messages
1,071
Reaction score
510
Location
SW Wisconsin
What state or country do you live in
Wisconsin
Rating - 100%
3   0   0
ok, I am just testing my tank water today. I do it weekly, I have mostly Hanna Checkers with some Salifert ones too. All relatively new. Anyway, the only test I have a question about is my Phosphorous/Phospate. My Hannah checker is the Phosphorous ULR test. I convert it using the chart and get a phosphate reading of .10 ppm on my Salifert Phosphate test, I get a reading of 0 ppm. So between the two I am reading 0-.10ppm. So which one should I believe? Or should I just say an average of the two? Thoughts?
 
i haven’t used it myself but I have read that the salifert phosphate test can be difficult to read below 0.1 ppm
I rely on my hanna phosphate ulr checker only currently. I have a tropic marin test too but I mostly only use the hanna checker
 
Most people trust the hanna ULR
 
I have yet to find a way to calibrate my eyes so I tend to trust the results from the Hanna checkers more. I know Hanna lists the accuracy of each test, does Salifert do the same?
 
ok, I am just testing my tank water today. I do it weekly, I have mostly Hanna Checkers with some Salifert ones too. All relatively new. Anyway, the only test I have a question about is my Phosphorous/Phospate. My Hannah checker is the Phosphorous ULR test. I convert it using the chart and get a phosphate reading of .10 ppm on my Salifert Phosphate test, I get a reading of 0 ppm. So between the two I am reading 0-.10ppm. So which one should I believe? Or should I just say an average of the two? Thoughts?

I'd stick with the ULR. :)
 
ok, I am just testing my tank water today. I do it weekly, I have mostly Hanna Checkers with some Salifert ones too. All relatively new. Anyway, the only test I have a question about is my Phosphorous/Phospate. My Hannah checker is the Phosphorous ULR test. I convert it using the chart and get a phosphate reading of .10 ppm on my Salifert Phosphate test, I get a reading of 0 ppm. So between the two I am reading 0-.10ppm. So which one should I believe? Or should I just say an average of the two? Thoughts?
I too am a Hanna checker fan! Easy and accurate
 
The Salifert test has the "higher sensitivity" option where you double the volume of water and double the reagents, which makes the perceived color darker. Then you halve the reading. This might make a 0.1 ppm reading easier to see since it would boost it near the 0.25 ppm reference on the color card.

But it's probably only interesting if you really want to compare the two out of curiosity or as a sanity check.

Otherwise just use the Hanna.
 
I use the Hanna...sticking with one and comparing the apples-to-apples results is more informative than comparing one test kit to another.
 
I’ve done hundreds of Hanna ULR phosphorus tests over many years. That’s the only one I expect I’ll ever use. Corresponds nicely with my occasional ICP.
 

WHAT’S USUALLY THE FIRST CLUE THAT SOMETHING IS OFF IN YOUR REEF?

  • A fish’s behavior or appetite changes

    Votes: 12 15.8%
  • A coral looks different or stops opening normally

    Votes: 46 60.5%
  • Water clarity or surface appearance changes

    Votes: 11 14.5%
  • Equipment sounds or flow seem different

    Votes: 8 10.5%
  • A test result catches my attention

    Votes: 16 21.1%
  • Algae or other growth starts changing

    Votes: 15 19.7%
  • I usually notice when the problem is already obvious

    Votes: 4 5.3%
  • It depends on what’s going on

    Votes: 16 21.1%
  • Other (Post in the comments)

    Votes: 1 1.3%
Back
Top
Home
Post thread…
Market
What's new