Anyone ever drilled an established reef tank without draining it first?

[skinz78]

Well yesterday afternoon I figured I would "fix" my leaky overflow situation on my 210g tank and in the process I broke my glass overflow... So I had to remove it and put a bulkhead into the hole through the side of the tank. Problem is that the previous owner of the tank only had a hole drilled that will accept a 1" bulkhead, and now my return pump is too much and it can't drain quick enough plus the hole is like 7" down from the top of the tank....

So here is my proposed plan...

Drain the tank down to just below the hole, get a 1" threaded plug and plug the hole with the bulkhead and pipe cap.

Then re-drill a hole up higher that will be big enough for a 1.5" bulkhead.

Here is my worry...

The current hole is in the end of the tank and when I set it up I placed the tank right up against the wall. Which is fine with me, just means I have to put the overflow in the end of the tank again. Since the tank is full and I don't have any desire to drain the tank to redrill it, I'm thinking of drilling it from the inside out and just take a maxi jet powerhead and put a hose on the outlet of it, and have a helper hold the hose on the drill bit when I drill the tank out just to keep the bit cool while drilling.

Now my concern is the glass chard's from drilling going into the tank. I wouldn't think it would harm anything because in the past when I've drilled tanks the chard's seem to just be a fine powder. Am I over thinking things here?

Any other concerns that I should be aware of?

 

[Aquaph8]

Your braver than me. Good luck man, be careful.

 

[skinz78]

LOL It's kinda a must do... Unless I buy a valve and tone down the return pump.

 

[skinz78]

Anyone?

 

[Reefing Madness]

Is your tank away from the wall enough that you can install an outter glass box overflow? Its easier to install one of those, as you just lower the water enough tonot get the new box wet as the silicone is drying. Then in the overflow box you can have the bigger hole drilled for the flow you want, instead of using that exsisting hole, and bringing it down a notch with a bulkhead.

 

[frank c.]

yes i drilled my tank w/ everything in it and big 2'' bulkhead. drained down about 4'' below projected hole duct tape back of tank where hole was going to push through drilled very slowly w/ super light drill pressure using salt water in a spray bottle wetting often and take your time don't be in any rush let the drill do the work all worked out perfectly, would have no problem doing it again.

 

[Fin]

I have seen pictures of people doing this sort of thing successfully, but I personally would not attempt this in my living room - and I have been drilling tanks for about 30 years. I wish you luck.

If you are worried about the debris getting into the tank, maybe get a large filter sock (without the ring) and duct tape it just below the area you will be drilling. It should catch the debris from the site and allow the water back into the tank, less most of the drilling debris. I would also use a new drill bit and a good cordless drill for this sort of thing. Maybe video this for everyone to see how you accomplish it.

 

[skinz78]

Is your tank away from the wall enough that you can install an outter glass box overflow? Its easier to install one of those, as you just lower the water enough tonot get the new box wet as the silicone is drying. Then in the overflow box you can have the bigger hole drilled for the flow you want, instead of using that exsisting hole, and bringing it down a notch with a bulkhead.

No it's right next to the wall.

yes i drilled my tank w/ everything in it and big 2'' bulkhead. drained down about 4'' below projected hole duct tape back of tank where hole was going to push through drilled very slowly w/ super light drill pressure using salt water in a spray bottle wetting often and take your time don't be in any rush let the drill do the work all worked out perfectly, would have no problem doing it again.

Did you drill from the inside out?

 

[frank c.]

as long as you can get to the back to do the work needed after, make sure to duct tape back where hole is going to be and yes use a newer bit, and i drilled from inside out drill on low speed, when you start to cut do it on a slight angle then gradually straighten it out, take your time can't stress that enough.

 

[stunreefer Verified Sponsor]

I've drilled many tanks for people that have established aquariums. Personally I drain down to only 10-12" of water in display. This helps take most pressure off of the seams - the tank will vibrate and shake quite a bit while drilling, especially when full. I use a spray bottle filled with RO/DI water to keep the drill bit cool. You really don't need to use a ton of water during the process. If any large shards/chips fall into the tank I pull them out when done, never had issues with the dust that occurs. Once finished install bulkheads, refill tank and fire it up.

Generally I drill from outside --> in but have been in a similar position as you, and drilled inside --> out same as described above

 

[trido]

I hate drilling tanks ever since I tried to drill a tempered 55 and it exploded half way through. I was surprised I drilled as far as I did.

Chris, you have some good advice posted above. Take your time and remove as much water from the tank as possible and you should be fine.

 

[skinz78]

Just went and bought the rest of the parts needed to do the job...

 

[Rob&Gab]

good luck bro. record the maddness! i wish you the best.

 

[Dashiki]

a guy in my area bostonreefers.org just did this. we all thought it was crazy but it worked for him.

 

[TropicalReefCorals]

This may sound kind of crazy, but I have drilled a lot of holes in tanks with a Dremel tool. You can pick up a 20 piece set of 1/8" bits for under $8 at Harbor Freight. It would be very easy to make an existing hole larger, as in your case. I recently drilled a sump with 1/2" glass for a 1" and a 1/2". With glass that thick, you need to take some time because the Dremel will heat up. I used a battery Dremel, frequently stopping and blowing compressed air through it to cool it down. My old corded Dremel worked a lot better before it died. I would advise taking some thick glass and practicing up before your first hole. You will be amazed how much pressure you can apply and how quickly it cuts. For cooling, I use a Tom's aqualifter pump and drip water near the hole, but you may need a helper if using this method on a vertical surface. I have used diamond hole cutters before, and this method is not as scary, and there is a lot less vibration and chance of problems. Try it!
Rick

 

[skinz78]

Fun times right now...

 

[skinz78]

Old hole and the new one above it.

 

[boehm742]

So just how nervous were ya?!

 

[skinz78]

LOL honestly not really, it just took forever to drill. I had to recharge my drill battery twice. It's all fixed now but it's a lot louder... I may need to install a ball valve in the line.

 

[Aquaph8]

Glad it went smoothly.