To drill or not to drill

[mpomfret]

Hi all. I am new to marine aquariums and new to Reef Central (1st post).

My primary question is: do I drill the glass for my overflow or use a siphon overflow instead ?

I have a 75gal (48x18x20) Oceanic glass aquarium that I am setting up. Uncertain as yet what I'll keep, but it will probably include SPS. The tank sits on a countertop and one of the short sides (18x20) butts up agains a cabinet. I plan to run the plumbing through this cabinet to the sump below. I bought a Mag 5 for the return and will hook up a shunt and ball valve so I can control the return flow somewhat.

My plan was to drill a hole for a bulkhead in the 18x20 wall and build an overflow box around it with acrylic or polycarbonate. However, when I called a local aquarium place to see if they could recommend someone to drill the hole, he said he didn't know of anyone that did that anymore due to liability concerns. He went on to say that drilling in the wall of a glass aquarium was a bad idea, particularly near the top as this is where the glass deflects the most and disaster would surely follow. He suggested an overflow made by SeaLife (which he happened to have in stock).

Other questions:
Does this guy have a point ? Am I really better off not drilling ? Or is he trying to scare me into buying something ? I understand that drilling a hole in glass means I assume a set of risks, but......
If I wind up unable to find someone willing to drill a hole in the tank, how painful is it to do myself ? (I am a woodworker with a garage full of tools and ~16 years worth of sawdust behind me, but working with glass is new).

Thanks for your help.

Matt

 

[PatMayo]

I don't have a solid answer for you as I do not have a lot of experience with this issue. I am due to upgrade to a 90 AGA that is already drilled etc.

What I can tell you is that there are several different types of overflows that are gravity fed etc. Some are better than others. The issue is that during power failures some are more prone to flooding than others. I would try to get as much information as you can before making a decision.

Regards,

Pat

 

[sjm817]

To Reef Central
Lots of people drill tanks successfully. Go to the DIY forum. There are many posts and guides for drilling a tank.

Step-by-Step: Drilling Holes in Your Glass Tank for Bulkheads

 

[ssgatbliss]

Not sure about the drilling but I run a Mag 5 on my 29 Gallon (from a 10 gallon fuge) and it's just enough. By the time the water makes the 24 inch + crawl up I'm only looking at about 300+ GPH. I have three small (120 GPH) powerheads connected to a wavemaker to help with flow. Minimum I would think you would want a Mag7 or even a 9 and put a flow control on the output if needed.

JMO

 

[sjm817]

3 - 5X display volume is the general rule of thumb for a return pump.

 

[Slackker]

I have no personal experience drilling glass. But, for what it's worth, In my experience, I have only seen broken drilled glass tanks. Not to say it can't, or isn't being done, but I've never seen a side drilled glass tank, that wasn't broken. I am victim of a tank breakage, and the risk of having 100gallons of reef in my living room again, is hard to explain with words...but just the fear of the smell haunts me enough to post...good luck

best regards
Brett

 

[jcraft]

I know quite a few people who have drilled tanks, I myself having owned two, and I know of no one's tank cracking after being set up and filled

keep in mind before you do anything that drilling the tank will void any warranty that the tank has, unless it is a custom job done by the manufacturer.

(my newest tank, a 30g cube was drilled for 4 holes . . . no breakage yet and im pretty confident that it wont)
peace of mind with a drilled tank is so much better than with a siphon that could break at any moment and flood your place

 

[jgoodrich71]

Also check if it is tempered glass. If it is tempered, it can't be drilled.

Built in overflows are much better that siphon, but get the tank made that way.

Even with someone experience with drilling the holes, there is still a possibility of cracking the glass. If you aren't a gambler, don't drill it.

 

[cracker]

I recently drilled the back panel of my tank and installed internal boxes. It wasn't difficult at all and The setup works SO much better in every way than the siphon overflows I used before. Sure I stressed but very happy I did it. Please consider drilling near the bottom and installing an internal overflow.A drilled tank allows for greater flow than the siphon type and internal boxes will give you much greater area for surface skimming than a bulkhead drilled near the top and fed with some sort of strainer.

 

[smcnally]

Have it drilled. I had a 75 gallon with CPR external overflow and I worried CONSTANTLY about it losing syphon and overflowing. I came home from work on numerous occasions and my water was covering my cross braces just about to go over. Now I have a 125 Gal reef ready tank and am worry free.

 

[mikeatjac]

Drilled. Less to worry about and it will free up space in your tank. You do need to plan out your holes for return, closed loop....

 

[mpomfret]

Thanks everyone. I'll kick this around on the DIY forum and see what happens. I'm still ambivalent; maybe leaning slightly toward drilling.

ssgatbliss: my bad. It is a Mag7 (not 5). It's been sitting in my cabinet for a couple of months while I work on the hood, other cabinets, electrical, etc and I forgot which one I had bought.

Matt