This is an aquarium food booster, excellent for reef aquaria that adds vitamins, lipids, fatty acids and other additives many fods often lack. Filters may be kept running, will not alter water chemistry. Does not contain yeast, phosphate or nitrates. This bottle contains a dropper. Helps cure lateral line disease. Mix with live, frozen or dried foods. For marine use only. Instructions: Shake well then soak any type of freeze dried or frozen food in .5ml of Selcon in plastic cup. After soaking, fill cup with water which can be poured directly into aquarium. Will cause initial clouding of water, benefiting all filter feeding invertebrates for several hours. For invertebrate tanks, add .5ml per 50 gallons of water. Can alse feed 1.0ml to a portion of live brine shrimp - aerate heavily - to enhance their nutritional value, then wait 12 hours before releasing them into aquarium.