API® PROPER pH 7.5 automatically sets and stabilizes pH at 7.5, removes chlorine and detoxifies heavy metals. PROPER pH 7.5 also contains electrolytes to reduce fish stress and promote Health General.pH is a measure of acidic or alkaline conditions in water, where a value of 7.0 corresponds to a neutral pH, pH values above 7.0 are considered alkaline, and pH values below 7.0 are considered acidic.