Aqua One’s Pharmaceuticals range is just what the doctor ordered for your aquarium! With the new extensive pharmaceuticals range providing all the necessities to keep your aquarium at optimum condition, finding what you need to keep your occupants healthy is now simpler than ever! pH is the measure of alkalinity and acidity within a liquid. pH measured on a scale from 0 – 14 with 7 being neutral, 0-6.9 is acid, 7.1 – 14 is alkaline. Each change in one pH unit reflects a tenfold increase or decrease in the pH value e.g. pH 10 is ten times more alkaline than pH 9 and one hundred times more than pH 8. It is therefore extremely important to make adjustments to pH slowly.