Test kits

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Testing is the one place where buying nice gear actually changes your results, because the number you act on is only as good as the kit that produced it. The split here is really about repeatability. A titration kit like Salifert gives you an accurate alkalinity reading if you read the color change carefully — and for a tank you keep stable with water changes, that's genuinely all you need, which is why it's the budget pick. The problem is the human in the loop: two people reading the same Salifert test can land a tenth of a dKH apart, and you specifically can drift over time without noticing. That's what the Hanna colorimeters fix. They remove the eyeball from the measurement and hand you a digit, so the trend you plot is real instead of a function of your mood and the kitchen lighting. We rate the Hanna alkalinity checker as the value pick because alk is the parameter you track most often and the one that moves fastest on a coral-heavy tank — a repeatable alk number is the single highest-leverage upgrade in this whole category. Calcium and phosphorus checkers follow the same logic if you're dosing two-part or chasing nutrients. The premium tier is for chasing specific problems: the ultra-low-range phosphorus checker for low-nutrient SPS tanks, Red Sea's multi-parameter kit if you want calcium, magnesium, and alkalinity from one box, and mail-in ICP for the trace elements no hobby kit can see. One honest caveat: colorimeters need fresh reagents and clean cuvettes, and a Hanna with old reagent is worse than a carefully-read Salifert. Buy the checker, but budget for reagent refills as a running cost.

Last reviewed 2026-09-30