For Phospate, the Salifert test kit is very hard to read and I would definitely not go there again. The D+D is much more accurate and an absolute doddle to read, you can't go wrong with it and no guesswork involved. It reads:-
0
0.008
0.015
0.03
0.045
0.06
0.08
0.11
0.14mg/l
I don't run any phosphate removers since starting Zeovit 3 weeks ago and my phosphate has already come down from 0.11 to 0.045 so am well chuffed.
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