Platform construction can be difficult in existing ponds. An alternative method is simply to place fertilizer bags in shallow water with the tops cut out. The bags serve to separate soil and fertilizer, and wave action will dissolve and distribute the fertilizer. Dilute liquid fertilizer with at least two parts water to one part fertilizer before application. In small ponds, liquids can be sprayed effectively from the bank with hand-held sprayers.
Boats make application easy in larger ponds.
You can spray the diluted fertilizer over the water surface or allow it to flow into the prop-wash of an outboard motor. Powdered formulations can be poured directly on the water surface. When Not To Fertilize Some ponds should not be fertilized. Mud prevents sunlight from passing through the water. Plankton must have sunlight to grow.