Holes in the bottom are a good idea providing that the box isn't sitting on the ground. A few holes up near the top will help with flow thru ventilation. Compressors generate heat and you want to get rid of that heat ASAP.

I would make sure that any valves that I used are the same I.D. as the air line or larger. I like the full flow ball valves.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).