Is there a problem with the Reagent Lot?

Hillbillyreefer · Mar 15, 2019

I picked up a new HI736 a couple days ago. The reagent lot included is Lot# H073 Exp:08/2020. Every test has shown 0 ppb,
Red Sea shows under .1ppm,
Hanna LR shows 0.03ppm
Lot# H082 for ULR shows 13 PPB.
It seems you have a bad lot of reagents out there. That’s very disappointing for a supposedly premium product. I bought this checker to alleviate uncertainty, not create more.

rkpetersen · Mar 15, 2019

The 736 is a phosphorus checker, not phosphate, and it reads in ppb. To convert to ppm phosphate, you multiply the reading by 0.0031.
So your phosphate is 0.04 ppm. The checker is working fine!

I generally like to keep my reading between 5 and 25.

Hillbillyreefer · Mar 15, 2019

It’s the lot number that reads 0 on every test that is the problem. Not the checker itself.

I should have been more clear that it’s the reagents I have little faith in, not the unit itself.