Salifert Phosphate Test Kit
2Hr Aquarist Commentary: Both the Nutrafin Phosphate Test Kit and Salifert Phosphate test kit are quite accurate for phosphates testing. Phosphates are produced by livestock waste and come in some tap waters. Aquasoil absorbs phosphates from the water column and this may cause aquasoil tanks to constantly read zero on phosphate tests. Plants rooted in the soil can still uptake phosphates from there. Generally, if you are dosing phosphates regularly through liquid fertilizer, one should not worry about the impact of getting a zero phosphate reading. Anywhere from zero to 5ppm are considered normal readings.
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