How close to rim can I drill?

[clancaster23]

I need to drill at least one hole in the side of my sump so I can put a bulkhead in there and have it lead out a short pipe into a spare tank for overflow protection. I got 3/4" bulkheads and the holes need to go as high as I can get them. This will be right at the existing water line. I'd like to be able to have the bulkhead touching the bottom of the rim of the tank. The sump is a 40 gallon breeder. The bottom of the hole itself would be 3 1/4" from the top of the tank. I will be drilling a 1 3/8" hole to accommodate the bulkheads. Is this ok to do this close to the top of the tank and would it be ok to drill two holes or should I just stick with one?

 

[kbuser92]

Either way should be fine.

 

[Aquarian]

If I remember correctly you want to be at least 1" from any edge.
http://www.inlandcraft.com/howto/drilling/drilling_aquariums.htm

 

[rrbigdog]

Does you tank have siphon breaks?

 

[clancaster23]

My tank was drilled weird. The overflow part only holds about eight gallons of water and it's drilled in the top middle of the tank. I have dual durso's. The returns are also drilled into the back of the tank, the center of the bulkheads are about 4" from the rim of the tank, one on both ends. I have no way of preventing about 30 gallons of water (the rim of the tank to the bottom of the bulkheads) in the case of a power outage. I only have a 40 gallon sump and can't get anything bigger in there so I have to put a couple spare 14 gallon tanks on each end and drill holes in the sump so that when the water raises as it's flowing down out of the tank that it'll have somewhere to go instead of my newly carpet/tiled floor.

I got one of the spares drilled out today and will do the sump tomorrow but I'm so nervous it's killing me.

 

[rrbigdog]

Can you provide a pic? I would think you could pvc it up...and then drill a siphon break. Just like a Reef Ready tank....but it comes from the bottom. Mine is 3/4 up to waterline then elbows to loc-line. Can tell without a pic if that is an option.

 

[clancaster23]

So you want pics of where my returns enter the tank? I'll see what I can do. Will post what I can here soon.

 

[clancaster23]

This is one of the returns. It comes out of the bulkhead and into a 45. From there there's the barb for the flex hose and down to pvc and through to the pump.

 

[clancaster23]

Just had a massive brain pain. Last resort instead of drilling my sump, I could just plug up the top two bulkheads like I did the middle two and make me some new over the top return pipes and put siphon breaks in those. This would let just the water above the break flow down and solve my whole problem the easy way.

 

[monique]

bravo- thats thinking. my great ideas usually come after the job is already done the hard way.