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A finely pulverized, water-soluble fertilizer containing 10% N, 52% P2O5, and 4% K2O was compared with a standard liquid fertilizer (10% N, 34% P2O5, 0% K2O) in ponds containing sunfish Lepomisspp. at the Auburn University Fisheries Research Unit, Auburn, Alabama. Our study suggests that sunfish production with water-soluble fertilizer can equal standard liquid fertilizer results at about 50% of phosphorus application rates of standard fertilization. Applications of 1–2 kg of P2O5/ha in water-soluble fertilizer at 2-week to 4-week intervals are sufficient to provide good sunfish production in waters with 20–40 mg/L total alkalinity, but rates of 4 kg P2O5/ha or more may be necessary in waters of higher total alkalinity. Low phosphorus applications to sport-fish ponds should be used with caution because phytoplankton blooms may not create enough turbidity to prevent excessive growth of undesirable aquatic macrophytes. On a nutrient basis, water-soluble fertilizers are about twice as expensive as liquid fertilizers. However, the water-soluble fertilizers can be used at a lower rate than liquid fertilizers, and they are more convenient to apply.