ANR-249, New Dec. 1990. John W. Jensen, Extension Fisheries Specialist, Professor, Fisheries and Allied Aquacultures, Auburn University. Fish Ponds Farmers know that proper fertilization can greatly increase crop yields. Similarly, pond fertilization can increase fish yields three to four times. Also fish will be in better condition, and catch by fishermen usually improves.
Fertilizers used in ponds stimulate the growth of microscopic plants called algae.
Phosphorus usually gives a much greater increase in fish production than either nitrogen or potassium. However, nitrogen in combination with the phosphorus is sometimes better than phosphorus added alone. Liquid fertilizers are superior to granular fertilizers in promoting rapid growth of algae in farm ponds. This is because the nutrients are already in solution, making them more rapidly available to the algae. Also, smaller applications of liquid fertilizers can be used, which may reduce the cost of pond fertilization.