Trying Polyp Lab's "System Reef-resh" this weekend.

[Ruth]

I use a Hanna colorimeter to test phosphates in my tanks and can attest to the inaccuracy or I guess inablility of the Salifert and other readily available test kits to test for PO4. I was shocked when I first got the Hanna to realize how much PO4 was actually in my systems that didn't show up on the Salifert.