During Black Friday Bulk Reef Supply was offering all of the Hannah checkers for $35, so I grabbed the Calcium, Alkalinity, and Phosphorus Ultra-low Range (ULR) checkers. I’ll take the time to do a write up on each of them eventually, but for now I wanted to make a quick note about how to make sense of the results from the Phosphate ULR checker.
The reading you get from the checker is parts per billion (ppb) of phosphate, not phosphorus parts per million (ppm). Conveniently enough for us, there’s an easy way to go from phosphorus (ppb) to phosphate (ppm). ..
Multiply phosphorus (ppb) by 3.066 then divide by 1000 to equal phosphate (ppm). Hannah also provides this handy look up table.