"Fixing" a drilled tank

[voiceinthedesert]

So I bought a 45 cube (24x24x18), been too hasty twice and am now trying to figure how best to rectify the situation.

The short version is this tank is drilled with two holes, one drain and one return. Both on the back a couple inches off the edge. That seems OK, except the tank did not come with an overflow box, just a strainer on the bulkhead.

So I think "no problem, I'll just get an overflow box."

So I get an Eshopps S Overflow. The mistake is that the hole is both the wrong size and too close to the edge of the tank for the box to fit even if I re-cut the hole over the existing smaller one (if that's even advisable).

So now I have two options. I can plug up the one hole and drill a second a few inches away, still as far to that side of the tank as possible. Or I can re-purpose that drain hole and have two return lines and put the overflow in the middle of the back of the tank.

The second option seems best at first glance, but I'm slightly worried that it's too small of a tank for that and the overflow will suffer from too much turbulence nearby (and maybe not get as good a skim off the top as I'd like).

Thoughts?

 

[Crabs McJones]

So I bought a 45 cube (24x24x18), been too hasty twice and am now trying to figure how best to rectify the situation.

The short version is this tank is drilled with two holes, one drain and one return. Both on the back a couple inches off the edge. That seems OK, except the tank did not come with an overflow box, just a strainer on the bulkhead.

So I think "no problem, I'll just get an overflow box."

So I get an Eshopps S Overflow. The mistake is that the hole is both the wrong size and too close to the edge of the tank for the box to fit even if I re-cut the hole over the existing smaller one (if that's even advisable).

So now I have two options. I can plug up the one hole and drill a second a few inches away, still as far to that side of the tank as possible. Or I can re-purpose that drain hole and have two return lines and put the overflow in the middle of the back of the tank.

The second option seems best at first glance, but I'm slightly worried that it's too small of a tank for that and the overflow will suffer from too much turbulence nearby (and maybe not get as good a skim off the top as I'd like).

Thoughts?

Are the two already drilled holes the same size? Another option could be to silicone on an overflow box over one of the holes with a bulkhead.

 

[Jakes2514]

If the two existing holes are equal size and location I would repurpose them as returns and put the overflow box in the middle. Drilling ‘close’ to an existing hole is not something I would like to take on and plunging just adds another potential point of failure

 

[Even Further]

On my tank I made an external box made from glass, siliconed to the back panel. On the tank inside I used a Modular Marine low profile acrylic overflow box siliconed to the inside. Its basically a ghost overflow without bulkheads.

Doing something like this will allow you to use the holes without modification/re-drilling.

 

[Daniel@R2R]

Tough problem. I'd probably return the eshopps overflow and try to get an overflow box made somewhere that matches the holes or do what @Even Further suggested. I'd pretty much do anything not to have to drill another hole .

 

[voiceinthedesert]

So the two bulkheads are not the same size, the drain one is larger (not sure on exact sizes as I'm not home at the moment). I've always had pre-drilled tanks before, so I was not aware a mismatch here was a problem?

I tend to agree that Even has the best idea regardless. Less drilling is always the least stressful option, I was just trying to come up with a way to use the stuff I already had. Probably not worth it.