I need help with measuring PO4

[Delphinus]

Looking for someone in the Calgary area to help me...

I need someone who has a Merck or D-D PO4 test kit, or a Hanna PO4 photometer to help me test my PO4 levels.

Here's my issue ... I HAVE the Hanna PO4 photometer but I suspect it is defective as I cannot get any readings with any degree of consistency. Ie. the numbers are all over the map. For example, I just took three readings on the same tank water and got 0.12, 0.04, 0.26.

Just to eliminate the possibility of user error, I need someone who can help me establish what my water PO4 really is.

Anyone? Please?

[andrewsk]

I am getting my New Hanna any day now. Ill let you know when it comes in.

Should be Monday and we can do a comparison.

[Delphinus]

Awesome. It would be great to do a comparison because I feel like a blind guy trying to understand what an elephant looks like.

[Delphinus]

Ok word to the wise, I just got some help on RC and I'll share what I've learned ... the instructions just say "mix gently" and then put the sample in. My lesson learned is, mix gently for like 2-3 minutes and then still do the 3 minute timed read.

I had asked Hanna technical support whether there should be residual powder before the test, they said yes, but no, you don't want any. I thought that didn't make any sense but that's what's been having me chase my tail. If I let the reagent dissolve completely then I seem to get consistent results. (Yay!)

[surgeonfish]

I just got my Hanna meter Friday. Love it already. I have been shaking the sample fairly vigerously for 60 sec and then testing and so far seems to work well.

[Delphinus]

Yeah ... see my problem was that not only do the instructions say "mix gently" (and not give any indication for how long), Hanna technical support themselves told me not to dissolve the sample. That advice was way off the mark, I should have trusted my instincts. Since last night I've done about 6 more tests and lo and behold .... consistent results. (Yay!)