How many bulkheads is TOO many?

[007]

I have an oceanic 30 gallon cube in the works . . . . I will be getting the back glass drilled for drain lines, return lines, and a CL intake.
This would entail a total of (1) 1.5" drain line, (2) 1" return lines drill on either side of the overflow, and (1) 1" CL intake for a total of 4 drilled holes (not sure where yet, but it won't be directly in line with any other hole).
Is this too many holes for a 20" x 20" x 5/16" sheet of glass?

 

[acrylic51]

IMO yes to many holes, but you might get away with it......

 

[007]

Thats kinda what I thought . . . I don't want to take any chances. Back to the drawing board . . . .

 

[thegrog]

I agree. You are probably pushing it with that many holes in a smaller tank. The more holes you have, the weaker the glass on that side will be and the greater chance for failure...not to mention leaks around the bulkheads.
Consider a corner overflow with a bulkhead drilled in the bottom for the drain line.

 

[007]

Cant drill the bottom . . . tempered glass.

 

[acrylic51]

I wouldn't really be concerned about leaky bulkheads.....If that is an issue use sched 80 bulkheads, but in turn your holes will have to be larger than sched 40.......

 

[007]

Yeah, the leaky bulkheads isn't really a concern, its more about the structural integrity of the glass.
I have decided that I am going to use a single 1" drain with an external durso standpipe. The returns are going to have to come up over the back glass.
I will still drill a second hole though for the CL intake.

 

[acrylic51]

Why so big on the drain hole???? Maybe if you scale the hole size down it might be doable depending the locations of the holes.

 

[007]

No idea . . . what would you suggest?

 

[acrylic51]

What are you planning on keeping in the tank?

 

[acrylic51]

1.5 is huge for something of that size.......If your only using 1" for your CL I don't see why you'd want 1.5 for a drain.....you could use a smaller bulkhead, but increase your durso stand pipe sizing.....Have you read his study work on pipe sizing and flow capacities on different size piping?

 

[007]

I'm actually planning on using a 1" bulkhead for the drain instead of the 1.5" . . . I realized that would have been overkill.

 

[acrylic51]

Honestly if it was me with the smaller holes I'd go for it.....I don't think you'll have a problem just space them out......and not close to the edges.....JMO

 

[007]

when you say smaller holes, what size are you referring to?
What about using a 1" drain and two 3/4" returns on either side of the overflow?
I have to stick with the 1" CL intake though.

 

[acrylic51]

Those hole sizes would be plenty IMO.....I would try it.....I don't think you'll have any problems.....Just drill slowly.

 

[007]

I guess I'll give it a whirl . . . . we'll see where it gets me. I think I am going to use some heavy duty bulkheads to be safe though (assuming the glass doesn't break while drilling!)

 

[acrylic51]

Get the bulkheads ahead of time....I'm sure you know sched 80 bulkheads are a little bigger than sched 40......That way you can use the bulkhead as a template and drill accordingly......