Kent Zoe is a superior vitamin complex for Freshwater fish and plants. (Zoe does not contain phosphates as most competing vitamin supplements do, and will not cause unsightly algae growth!) It contains aquaculture grade vitamins, meaning that they are still active after one year in your aquarium! It is unique because it also contains natural minerals from spirulina and kelp sources.Instructions:For live, fresh or previously frozen food, especially brine shrimp, soak in Zoe overnight, or add several drops directly to food prior to feeding. For dry foods, add several drops directly to food prior to feeding. To add directly to aquarium water, add 1 teaspoon, (1 capful, 5ml) per 50 gal. up to twice weekly. Adding vitamins to aquarium water will benefit plant life, but will only benefit fish indirectly.