The garnet suspension and removal system is very effective.  A large seal-less pump is used to to recirculate water between the tank and the filtration system, and using eductor nozzles at the bottom of the tank helps keep the sand in suspension.  The water/sand passes to a small centrifuge where the sand is separated and falls into a tank/liner.  The water is fed back to the waterjet tank.  This process happens continously.  An option for the system can be purchased which allows the water level to be raised and lowered slightly to allow the waterjet nozzle to be under the water level during cutting for reduced noise and reduced sand overspray.