JBL ProAquaTest Lab MarinMonitors the water values in marine aquariums simply and reliably. Determines: pH value, carbonate hardness, calcium, magnesium, copper, ammonium, nitrite, nitrate, phosphate, silicate, oxygen. Easy to use: add water to cuvette, add indicator, compare on scale count drops until colour changes. Comparator system takes the inherent water colouring into account. Incl. water analysis report sheets & pen. Childproof reagent bottles, waterproof plastic