API pH Down – Freshwater Aquarium pH Reducing Solution API® pH Down helps lower high pH levels in freshwater aquariums, making the water more suitable for fish and plants that prefer slightly acidic conditions. Its fast-acting, colorless formula is easy to use and will not cloud aquarium water. Product Benefits Lowers pH in freshwater aquariums Helps create suitable water conditions for fish and plants Fast-acting and easy to use Colorless formula Will not cloud aquarium water Phosphate-free and nitrate-free Does not encourage algae growth Why pH MatterspH measures how acidic or alkaline aquarium water is. A pH of 7.0 is neutral, above 7.0 is alkaline, and below 7.0 is acidic. Different fish require different pH levels to stay healthy, so regular water testing is important. When to UseUse when aquarium water testing shows that pH is too high and needs to be lowered. Usage ReminderTest aquarium water regularly and always follow the dosage instructions on the product label.