An all-water tank is a device designed to retain settling matters in domestic wastewater (wastewater from toilets, bathrooms, kitchens, laundries, etc).
A complete water treatment system includes an all-water tank and a waste disposal system (sand filter, spreading system, etc.). The pre filter integrated into the all-water tank is located at the output and filters the pretreated effluent. This pre filter warns the user that the all-water tank needs draining and protects the treatment device downstream (sand filter, treatment system) against premature clogging by retaining non-settled particles.