Salt with phosphates?

[roberts01]

A month ago i had a constant icrease of po4 and some algae growth, icreased water changes. Tested po4 with hanna phosphorus test and it was 0.1, added gfo and after a week po4 was 0.13. Today i did some tests, i took fresh rodi with 1tds added tropic marine salt and came up with 0.1

I had fm salt so i did the same and came up with 0.02 which is more than ok.

Could it be possible that the salt absorbed some moisture and fouled the salt? Or just bad batch?

 

[LiveWire]

Did you happen to test the RODI water itself to make sure that was not the source?

 

[roberts01]

Hanna gave false reading of 0.22, tested with red sea and it was ~0.02 i thought aswell about rodi but tds was 1 and all filters were changed recently.

 

[ryeguyy84]

Are you cleaning the Hanna cuvettes before you put it into the checker? No finger prints?

 

[Steven Garland]

I did once have a bucket of RSCP that tested off the charts on a fresh batch. Supposedly it happens in the Red Sea every few years to where the sediment gets stirred up and the salts become riddled with phos.

 

[roberts01]

I am cleaning the cuvettes, and i found a possible cause. It appears that the spectrapure silica buster was exhausted. I somehow read that it could be used for two years. I changed it a year ago.

So today i bought mixed bed resin mb400 and fresh deionization resin, coming out clean at 0tds, tested with hanna phosphate checker and came out at 0 po4.

But mixed a sample with tropic marine salt and came out with 0.13 po4

Second with fauna marin salt and came out at 0.02 po4.

So i think i had two things to blame.