PH & Alkalinity in Water

Maintaining the water chemistry of a saltwater aquarium is one of the best ways to keep fish healthy and happy. Balancing pH levels with the proper alkalinity can be tricky for the novice aquarium keeper. Monitor water chemistry and change water frequently for optimum health.

  1. pH

    • Power of hydrogen, known as pH, is the measure of the acidity or alkalinity of aquarium water. A pH reading of 7 is neutral, neither acidic nor alkaline.

    Alkalinity

    • Alkalinity measures the calcium hardness of water. More alkaline water is less prone to rapid pH changes.

    Normal Readings

    • For most aquariums a pH level between 8.1 and 8.4 is normal. Reef aquariums are more sensitive to pH changes and fare better with a higher pH level.

    Alkalinity in Seawater

    • In nature, alkalinity is maintained through natural buffers like calcium, carbonate, borate and bicarbonate.

    Home Monitoring

    • Home aquariums do not have natural buffers, so aquarium keepers should monitor pH levels daily. If pH levels begin to drop rapidly, add baking soda to the water to increase alkalinity.