How much space 4 bulk head?

[Gordonious]

<DD>I need to find out how close I can get to the edge of a 20gallon high all-glass tank with a drilled 1 1/8” diameter hole for a bulk head. I am hoping I can get with in The reason why I am asking this is a bit complicated, but I'm hoping I can start cutting the hole ~~ 1 3/8" from the side.

 

[Gordonious]

<DD>I have just had an epiphany. I have very little room in my sump. My father and my uncle helped my build the stand and I am just not giving it up. Down below there is floor space of about 27 3/4" X 25 3/4". This is just barely enough room for two 20gallon highs. My plan for a while had been to put two 20 highs back to back with a backing between them so you couldn’t see through. The back tank would be the sump, the front an additional display. The 20s are less then 27 3/4" wide, but I had not realized I could use all this space. In part of it there is a board that limits the height to about 1 mm taller then the 20highs. This wouldn’t allow me to put a full hood on it or even a lid, however for the sump I don’t need a full lid or lighting. So now I have the ability to stagger the tanks.

<DD>This is huge because with tanks back to back it was difficult to find a safe way to stager them together. The extra room allows me to drill the tanks so they can over flow into each other if need be. (Likely the display into the sump in which it would be pumped up to the main display.) Here is a rough draft picture (don’t laugh I will change this when I can):<BR>

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