for the inflow to the bulkhead, you want to secure the PVC into the bulkhead with PVC primer and glue, in this case the exterior threads will not be used. For the locline inside the tank, you need to purchase a fitting that screws into the bulkhead thread and converts to locline fittings, I used this:
Loc-Line flexible modular hose offers endless plumbing configurations and is useful for unique plumbing designs. Loc- Line Modular plumbing is most commonly used on return lines and closed loops where it is important to direct the water flow in a particular direction. For 1/2" Loc-Line NPT...
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