Copper aid is safe and efficient external parasite treatment for fresh and saltwater. Popular treatment for Ich & velvet. Just 1 teaspoon per 4 gallons of water. Treats water for 1 month. No water changes, temperature or pH level adjustments are required prior to treatment. Maintain all normal filtration and air flow. Replace carbon after completion of the treatment. During water changes, treat replacement water with copper-aid. For ornamental pond and aquarium fish use only. Not for human, medical or food fish use.