Description: Brightwell Aquatics Phosphat-E 500mL Eliminates Reactive Phosphate from all Marine Fish & Reef Aquaria.Overview: Begins to eliminate reactive phosphate immediately upon addition to aquarium.Safe for all inhabitants of reef and marine fish-only aquaria.Each ml eliminates 1 ppm phosphate in 4 US-gallons of water.Helps facilitate the removal of phosphate from aquaria during periods when dissolved organic material is abundant.May be used on an ongoing basis to help control phosphate in heavily-stocked aquaria.Over 50% stronger than most competing products.Formulated by a marine scientist. Technical Background:Phosphate, while required in miniscule amounts by living organisms for proper functioning, can indirectly negatively impact the overall appearance of an aquarium system if it is allowed to exist at a concentration measurable by most aquarium test kits (e.g. >0.05 ppm); in order for this impact to occur, other undesirable substances must be present in varying concentrations, however these substances are rarely limiting in the typical marine aquarium. Because of this, elevated phosphate concentrations, whether sporadic or chronic, should be combated. Phosphāt-E enables a quick solution to elevated phosphate concentrations by binding the reactive (“free”) form of the molecule and making it unavailable for biological uptake. The resultant inert phosphate compound (a particulate) may then be permanently removed from the system via mechanical filtration and/or protein skimming. This method of treatment may be used as needed and/or on a continual basis to maintain an immeasurable phosphate concentration in a marine aquarium. While Phosphāt-E provides a workable solution to potential phosphate-related problems, it should not be seen as an alternative to proper and sensible aquarium husbandry. Aquaria with extremely-low to immeasurable reactive phosphate often appear more pristine than those in which phosphate is allowed to persist in an elevated concentration. Feeding aquarium inhabitants sensibly, limiting the use of organic-based supplements and additives, use of a high-quality synthetic aquarium salt blend, and performing water changes/replacing evaporation with purified water are all important aspects of phosphate control. Additional means of limiting phosphate are maintaining a culture of macroalgae in the system to naturally deplete phosphate and other substances, and/or the use of an effective and well-maintained protein skimmer.Notes: Phosphate test kits may show a false-positive reading after aquarium has been treated; this is a result of the chemical mechanism by which phosphate test kits operate and does not indicate that the product has failed to perform its intended function. The higher the percentage of bound phosphate removed by filtration, the more accurate test kit readings will be.Instructions and Guidelines:Aquarium may become slightly cloudy when product is first applied; cloudiness is temporary and will dissipate. Determine phosphate concentration in aquarium prior to first use by testing with an accurate test kit. Add product to aquarium near a mechanical filter or protein skimmer intake at the maximum rate of 5 ml (1 capful) per 20 US-gallons daily for each 1 ppm of phosphate present in system. When used in this fashion, 250 ml treats up to 1,000 US-gallons (3,785 L). Add weekly at same dosage to maintain an immeasurable reactive phosphate concentration.Ingredients: Purified water, proprietary phosphate removers.Size: 500 mL