The Effects of Copper on Saltwater Fish

Copper in saltwater aquariums can be beneficial or detrimental depending on the levels. Very low copper levels will hep control algae and parasites in aquariums, but certain marine organisms can't tolerate any amount of copper. Copper exposure can put the health of aquarium life at risk.

  1. Cryptocaryon Control

    • Cryptocaryon, commonly known as ick, is a protozoan parasite that can make saltwater fish ill. Add very low amounts of copper to a saltwater aquarium to kill this parasite, but be aware of the risks. Do not use copper in a reef aquarium or in tanks with invertebrates. Use a test kit to make sure that ionic copper levels do not rise above .2 ppm (parts per million). Do not treat for more than seven days.

    Extended Exposure

    • Extended exposure to non-lethal copper levels damage gills and compromise the immune systems of saltwater fish.

    Toxic Levels

    • Most invertebrates die when exposed to copper at any level. Other saltwater fish may die when exposed to high copper levels. Even therapeutic levels for parasite and algae control can kill some saltwater fish.