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Before Fertilizing, Test Your Pond for Water Hardness

If you have a pond and are planning on applying any fertilizer to your pond this year, now is a good time to have the water hardness of your pond tested.  Testing pond water for water hardness allows the determination of whether your pond needs limed or not. If the pond water is too soft, fertilization will have little to no effect and be a waste of time and money.

Georgia receives a large amount of rainfall on a yearly basis and many of our ponds are filled and maintained by rainfall flowing into the pond from the watershed. Rain water is often fairly soft or has low water hardness. Unless liming was done to the pond prior to be it being filled or the pond has not been limed in several years, chances are that your pond will have low water hardness.

Water hardness testing is offered at the Jones County Extension Office free of charge. We can determine the water hardness and provide you with the lime requirement of your pond. Water hardness is measured in parts per million. Ponds with extremely low water hardness can require more than a ton of lime per surface acre. For fertilization to be the most effective and to develop a bloom of plankton in your pond, the water hardness needs to be 20 ppm or higher.

To achieve the water hardness of 20 ppm, apply bulk agriculture lime to the pond surface. A broadcast application is the best method of application if possible. When broadcasting the agriculture lime, be sure to lime the entire pond surface. Upon the completion of liming the pond, it may take up to 3 months for the hardness to start to improve. Rainfall or soft water entering the ponds may also dilute the lime and a subsequent liming application may be required.

If you want your pond water tested, please bring a pint of water to the office. For more information on pond management, feel free to call the Jones County Extension Office at 986-3958 or refer to publications on the UGA Website.