NATURAL, CHEMICAL FREE SOLUTION FOR A CRYSTAL CLEAR, HEALTHY AQUARIUM – Pure Aquarium contains beneficial bacteria and natural enzymes that rapidly break down organic waste leaving your aquarium clean and fish healthy. REDUCES FILTER AND TANK MAINTENANCE – By naturally removing excess fish waste, fish food and toxins, Pure Aquarium helps your water stay fresher for longer, meaning fewer tank maintenance sessions and happier, less stressed fish. CONTINUOUS GRAVEL CLEANING AND WATER FILTERING ACTION – Simply adding 1 to 2 Pure Aquarium balls per 25 litres of water once a week, Pure Aquarium reduces sludge and organic build up on gravel ensuring that your fish can thrive in a safe, healthy and crystal clear environment. SAFE FOR ALL FISH AND TANKS – Pure Aquarium’s all natural ingredients only activate when needed and are safe to use in new or established aquariums. AWARD WINNING PRODUCT, MANUFACTURED IN THE UK – Twice awarded product of the year by Practical Fishkeeping.