Closed Loop Plumbing

[Jadinop]

In my opinion you are really pushing it with such thin glass. Your initial post of " Can I drill four 1in holes in the bottom of a 40 gallon" has really changed to a point where I don't think it will work anymore. I think your biggest problem will be with the two 1.5 in drains. The weight of the water filled pipe and wide flange of the bulkheads will put a lot pressure on the glass. Being located close to the middle of the pane will really increase this effect. The slightest bump or vibration will probably be enough to crack the rear pane in half.

Just to make it clear, this is what you want to drill in a 40 gallon tank. This is by actual hole size not the size of the pipe that fits in the bulkhead.

4 - 1 3/4 holes in bottom
2 - 2 3/8 holes in the back for cls supply
1 - 2 3/8 hole in the back for overflow drain
2 - 1 1/2 holes in the back for returns

[nnewhouse]

Yes thats correct on the holes. It sounds as if you think it might be too much. What would you recommend? Smaller pump, fewer holes. . . . . etc.

[ckusnierek]

Another thing to consider is that most tank are tempered on the bottom.
not sure about a 40 but most are. Also that Dart will need a 2" feed that a 2-7/8 hole.

Here is what I did on my 125.... I drill 4 holes for 1" bulkheads and 2 holes for 1.5"(feed) then teed into a 2" fitting and I used PVC came down off the back and to the front. Then I just covered the PVC with rockwork.
Just another idea....

[ckusnierek]

I dont think I dart is too much of the nozzles are positioned right. I have a friend setting up a 60 cube and he used a dart and then added a Vortech MP40 that's the dart(3700) + the MP40(another 3000). He is also using a OM 4 way and so am I. If you can afford one I highly reccomend one...

[nnewhouse]

For the dart feed I was just going to "T" the 2-1.5" bulkheads to a 2" pipe. That is a cool idea for the returns! I want a really clean looking back to the tank. That is why I am wanting to drill the bottom. This 40g is not tempered. I specifically ordered it that way. That's why I got the extra thick bottom.

[ckusnierek]

So you are going to have 4 1" bulkheads and 2 1.5" bulkheads all on the bottom of a 40B?
I think you will have a combination if water,glass,rock and coral on the floor....

JMHO

[nnewhouse]

No. The only holes I am going to have in the bottom are the 4 1" bulkheads. The others are going to be on the back.

[Jadinop]

I think the problem that you will have is with the back pane of glass. Between the cls supply, overflow and returns you are going to end up with some close together holes. Any chance of moving the returns or overflow drain to the sides?