Plumbing Ideas Please

[coachd]

I just bought a 165 gal tank and I am needing some help on how to do the plumbing on the tank.
The tank is drill on the back of the tank. There is a large built in overflow in the middle that has three outlet holes. There also is three return holes. One in the upper left corner, and one in each of the bottom sides.
Some questions I have are .............
Will bulkheads work in the bottom return holes without leaking, if not what suggestions ?
The guy I bought the tank from said that he used the two bottom holes along with two of the holes from the overflows as a closed loop system, good idea or is it better to use all three outlet holes to go to the sump?
My LFS, who I did not buy the tank from, said he thought I should cover the two bottom return holes with glass, basically seal the holes up, and use the top return hole and run another return line from behind the tank. Does that sound reasonable?
I will be running a 55 gal Ref/sump
Any ideas on this setup would be appreciated :help:
I hope I explained my questions where you can understand them? Thanks

 

[coachd]

I looked at the closed loop SCWD that is on melev's reef site. That is real similiar to what I would like to do.
Would that design work an my larger system?
Would I need to use two of the three outlet holes to create enough waterflow?
What size pump would I need? Can you go too big on the pump?
Would I use bulkheads to run the pipe back through the return hole?
Sorry for all of the questions. When I got into this hobby I wanted to keep wonderful fish, not learn how to be a plumber.

 

[92protruck]

can you post a few pics or a drawing of what you are talking about? I just can't picture it and maybe someone will be able to help you better with pics.

 

[dogstar]

How much total flow do you want in the tank? like 15X, 20X, ect.
And can you list the size of the holes and overflow box ?
This is how I understood you post >>>>

 

[coachd]

Dogstar
Your drawing is very close except the overflow box is located at the top of the tank with the three outlet holes.
I will not have the tank at my house until Monday night and then hopefully I can fiqure out how to post some pitcures of it.