I used hard pipe with a ball valve to a sock, I tee'd to a refugium. If you don't haVe a refugium, the tee is still good, because you can bypass the sock, for whatever reason. Sock cleaning, feeding, just because you heard some are sock less, part time,. I used a 1 inch compression to double ended splice that I bought at the home supply. Be careful not to glue a fitting that blocks the bulkhead fitting from being serviced. It need to be removable. I glued in a segement of 1 inch pipe into the bulkhead drain slip fit and attached the compression fitting Then I glued up the rest of the supply manifold. I have seen a one sided compression fitting . there is a compression to slip fit somewhere out there. It's the best because it give head room.
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