Aquarium Systems Test Kit A new range of test kits from Aquarium Systems that accurately test your aquarium water. Phosphate is an end product of the decomposition of organic material such as fish waste, plant material and uneaten food, and excess levels can promote unwanted algae growth, the Seatest PO4 phosphate test kit allows accurate monitoring of phosphate levels, indicating occasions when water changes may be required. The kit contains up to 40 tests for long use and peace of mind. Suitable for marine and freshwater aquaria Please note this product is short dated - BBE August 2015.