Mike,
Where the PVC went through the bottom pieces I tapped them and used MPT fittings to thread through them till the fitting was tight against teh acrylic. Then put a FPT over the open thread which the spray bar is attached to on the outlet side. THe intake side for the pump is a FPTxFPT 1/2" 90 degree elbow with a 1/2" nipple through the acrylic. To ensure a seal I ran a bead of Weld on around the PVC. Where the PVC goes into the pump is a bit more complicated. lol
There is a threaded 90 in there. Into the 90 I put a 1/2" threaded barb. Onto this threaded barb I wrapped a rubber sealant tape around the barb. This taped end was threaded into a 1/2" FPTx 3/4" slipxFPT Sched 80 fitting. This was then slid into a 3/4" slipxslip fitting which has two 1/4" tapped holes for the CO2 intake/water in and the recirculation loop. Into the other side of the slipxwslip fitting goes a second 1/2"FPTx3/4" slip fitting into which a 1/2" nipple goes in. Attched to that is a coupling shich is threaded into the pump. Confusing huh? here's a picture. I can't really explain it any better. Really. lol Wht that whole last bit does is creates a venturi. A small one. But enough to ensure that there is suction going into the pump. This pulls water in from the recirc loop and also assists with the intake of water and CO2 to a small degree I think.
