WATERRO AQUARIUS 400G-H3013-DI reverse osmosis system (membrane in housing) WATERRO AQUARIUS 400G-H3013-DI is a high-performance reverse osmosis system specially designed for freshwater, marine and reef aquariums requiring large quantities of ultra-pure water with minimal total dissolved solids (TDS). Thanks to its 400 GPD reverse osmosis membrane and integrated deionisation (DI) stage, the system provides high-quality RO/DI water even for the most demanding aquariums. The system uses SLIM 10" pre-filters for effective water preparation before the reverse osmosis process. Primary water purification is performed by the WATERRO WR-3013-400 reverse osmosis membrane, with a capacity of up to 400 GPD, while the SLIM 10" deionisation cartridge completely removes residual ions and minerals, producing ultra-pure RO/DI water. The system operates without a booster pump or storage tank, making it economical, quiet and easy to maintain. Standard SLIM 10" filter housings allow filters to be replaced easily and reduce operating costs. WATERRO AQUARIUS 400G is a reliable solution for aquarium enthusiasts and professionals who require large quantities of exceptionally pure RO/DI water and ideal conditions for fish, corals and other aquatic organisms.