The Effects of High Phosphates on Saltwater Fish

Keep phosphate levels low to promote the health of your saltwater fish. As waste products and leftover fish food accumulate in the tank, phosphates are created as the organic matter decays. To prevent high phosphate levels, don't overstock a saltwater tank or overfeed the fish.

  1. Slime Algae

    • Slime algae feeds on phosphates. When phosphate levels are low, the corals, anemones and coralline algae prevent slime algae by consuming the small phosphate amounts that are present in the saltwater aquarium. Without high phosphate levels, slime algae can't establish itself in the tank environment.

    Low Calcification

    • High phosphate levels restrict the calcification of saltwater aquarium reef systems. This prevents healthy growth of corals, invertebrates and coralline algae.

    pH Levels

    • High phosphate levels make pH levels increase, which can cause stress to saltwater fish. Saltwater fish can die or become ill from pH levels that rise suddenly or are more than 1.5 points above the correct levels.