I just put together an external box with a Iwaki Md-30RZT, Criticool Waterplant res, and 2-342. Unfortunately, I think the restriction of the inlet by the barbs on the Waterplant is causing the pump to cavitate because it is extremely loud (I can hear it throughout my house), bubbles are coming from the outlet, and when I throttle the outlet the pump gets quieter. To remedy the situation, I ordered from mcmaster a 2'' OD 1.5'' ID clear acrylic tube and clear acrylic discs which I will fashion into a res that will fit directly over the pump inlet. The other end of the new res will be a 1/2'' od barb. Should this be sufficient in preventing further pump cavitation? Also, what should I use to seal the area around the new barb and the pump inlet in the new res, and what should I use to bond the acrylic.