questions re: hole drilling

[danny zubot]

I'm concerned about the integrity of the glass of my 3' cube in regards to having holes drilled for a closed loop. The tank is 36 x 36 x 20" tall and uses 3/8" glass. I was hoping to drill 3x 2.5" holes for 1.5" bulk heads on the back glass, plus another of the same size for the overflow and one more smaller hole for the return.

The overflow and return holes are top right and top left, and don't concern me so much. The closed loop holes I though would be evenly spaced across the back but staggered slightly in their hight. I'm concerned about whether or not three 2.5" holes in 3/8" glass that are 9" a part will create week spots running across a 36'' pain? Does anyone out there have a similar tank that they've drilled closed loops into that can ease my mind about this?

[danny zubot]

Question #2.

What about drilling 1.5" holes into 4" euro bracing? Good or bad?

[SeaHorse_Fanatic]

If you're so worried about glass integrity, why not just add a couple of Maxijet mods. It'll be cheaper, less power, and less heat, without the worry.

Anthony

[digital-audiophile]

Have you thought about putting in an overflow box and drilling the drain/return lines on the bottom to go Herbie style?

[danny zubot]

Herbie Style?

[danny zubot]

Anthonie, My other option might be a wave box or some other kind of higher end flow maker. I already have the pump for the closed loop so I'm exploring that option first. :biggrin:

[digital-audiophile]

Herbie is the best thing going right now :)

I keep linking to Richards build thread because it does an awesome job of showing how it is plumbed http://canreef.com/vbulletin/showthread.php?t=37356&highlight=herbie

Here is the reef central link that created this style http://www.reefcentral.com/forums/showthread.php?threadid=344892 lots of reading if you are up to it.

Basic concept though is the tank is drilled with three holes on the bottom of the tank in the overflow. Two holes for 1-1/2 pipe, one is the primary drain that is throttled with a ball/gate to eliminate and splashing, gurgles bubbles etc, the second is an emergency drain line just in case the primary is blocked for any reason. The the third hole is for the 1" return line. Take a look at Richards pics they show really well how it is plumbed.

You are more than welcome to swing by my place to see how I have mine hooked up if you are interested :)

[danny zubot]

Hmm, interesting system. I might have to consider it.

I just spoke with Bow Valley aquariums and they recommended that I don't drill closed loop holes in the side glass, too thin. They did say that the bottom on my tank was sturdy enough for those sized holes, so I start thinking about a new design.

Digital, I might have to come over to see yours after all.

[danny zubot]

My new thoughts about this were to drill all of the holes through the bottom, which is 1/2" glass. So I'm thinking of the four holes for the closed loop and drain, plus another smaller hole for the return. How far apart do these holes have to be? If they have to be any significant distance I could be looking at a coast to coast overflow.

I don't really want a coast to coast overflow because with a 4" eurobrace I would have to have it extend 7" out from the back of the tank in order to be able to still reach into the overflow. I'm still debating just taking the tank back to have them replace the back panel with 1/2" glass so that i can drill it.

[mark]

If going coast to coast, could the bulkheads and fitting be installed before the bracing or overflow mounted? For clearing how much room would one need for a tooth brush or a spong on a stick, a 1"?

[danny zubot]

The tank is already assembled so I'm stuck with what I have right now. i wanted to be able to get my arm in there just in case I need to catch a fish or loosen some plumbing or whatever.

I just did the math. if I go coast to coast I go from 112 gallons to 91. Not worth it IMO. I think I'm going to have to bite the bullet and take it back to have the heavier glass put on.

[BCOrchidGuy]

Danny, I built an outside overflow for my 60, I went with 1/4 inch glass, and did it 3 inches wide, next time I'd go at least 6 inches wide to make it easier to put my hand in. I simply cut the top of the tank with a 3/4 inch lip, the water flows over the top into the box and I have TWO down tubes going into my sump. It works nicely doesn't take away from the tank capacity and allows shrimp larvae to stay away from preditors. This does not address your desire for closed loop though.

Doug

[BCOrchidGuy]

How about siliconing on some glass plates behind the glass with larger holes drilled in them. It would (I assume) distribute any stress from the hole and support the glass of the main tank. I've repaired a number of small tanks by siliconing on a plate large enough to cover the crack and never had a leak however I haven't tried it on anything larger than a 33 gallon.

Doug