Basic plumbing question: capping a bulkhead

[stgla]

I am turning a reef-ready acrylic tank into a sump so I want to cap 6 bulkheads. The bulkheads are female threaded on the dry side and I don't care if they stick out a bit.

Can I just put MPT caps in there? Do I need to use tape to prevent leaks?

The bulkheads appear to be schedule 80 (gray). Does that mean the caps have to be sch 80 also?

Thanks.

 

[Vinny Kreyling]

Caps can be used, schedule 40 should work, use a sealant not tape.

 

[stgla]

Oops I meant to say plug, not cap. I tried a sch40 and it goes halfway in by hand but I wonder if I try to tighten too much will it crack the bulkhead.

My other problem is that one of the bulkheads is missing a nut. Will stores sell me a 1" threaded nut without my having to buy the whole bulkhead?

 

[mcgyvr]

Oops I meant to say plug, not cap. I tried a sch40 and it goes halfway in by hand but I wonder if I try to tighten too much will it crack the bulkhead.

My other problem is that one of the bulkheads is missing a nut. Will stores sell me a 1" threaded nut without my having to buy the whole bulkhead?

Hand tighten then 1/4 to 1/2 turn with proper non-hardening thread sealant should be sufficient.. If sch80 its unlikely you will crack it and often times those are PVC vs ABS and can take more "abuse" but still thread sealant + hand tighten + 1/2 turn and done..

Never seen just the replacement nuts sold separately.