ZEROPHOS DOLCE Phosphates derive from the decomposition of food residues, plant remains and fish wastes. In small amounts, phosphate is necessary for plant development, but an excess promotes the proliferation of algae. Apart from being unattarctive, algae can hinder plant growth. ZEROPHOS eliminates phosphates in 48 hours and keeps their level at an adequate concentration for plants. ZEROPHOS effectiveness varies, depending upon the amount of phosphate initially present, and the rate at which new phosphate is produced by decomposition. This, in turn, depends upon the population density and on the efficiency of the filter system. For this reason, we advise checking the level of phosphates periodically to determine the optimum schedule for product replacement. ZEROPHOS does not alter pH and is harmless to the aquarium's inhabitants. It also reduces the amount of silicates dissolved in the water.