Kent Pro Tech Coat Marine neutralizes chlorine and heavy metals. It restores the natural slime coating to relieve fish stress, calm, and protect against abrasion. It helps acclimatize fish to new surroundings. It can be used when preparing tap water, making water changes, adding new fish, handling fish, transporting fish, or when fish are wounded. Pro Tech Coat Marine is different than competing products because it contains only costly polyvinylpyrrolidone as the coating ingredient. This same product is FDA approved as an ingredient in human medicinal and nutrition products. Competing products contain cheap fillers such as aloe vera and carboxymethylcellulose which then decay in the aquarium and lower the redox and the overall water quality. Pro Tech Coat Marine does not affect biological filtration and is safe for all marine species including sensitive hard and soft corals and other invertebrates. Competing products may cause soft corals and feather dusters to close permanently.