I will soon be upgrading from a 55 to 90 gal tank. I have been putting much thought into drilling the new tank to make a closed loop system. I have even bought the drill bits for it but dont have the tank yet. Just wondering if anyone has some advise or experience in doing so. I have seen some closed loop systems in undrilled tanks that look ok and would be relatively easy. Im not even sure as to how many or what pattern to make the holes either. I was thinking of using a mag or ehiem pump also. Anyone have some suggestions.
to drill or not to drill
- Thread starter jwess
- Start date
got2lb
New member
DRILL IT!!!
I didn't drill mine and I'm getting real tired of having to fix the siphon on my HOB overflow all the time. Plus then I wouldn't have to have these big seios in my tank moving the water around.
Glaspie69 has drilled a few tanks and so has waverz both of them are close and could give you some pointers i'm sure. Just make sure the tank isn't tempered before you drill! Are you going to use the 55 as a sump?
I use a mag 12 as a return pump (sumbersed, not external) I don't really have any complaints about it. It's way too big for what I need and I have to keep it throttled way back. The eheim's are supposed to be awesome pumps though, can't even tell they're running.
I personally would get a pump that's made to run external to use on a closed loop that way it has a fan to cool the motor down and you don't put all the heat into the tank.
If you need help moving anything around or something just hollar!
I didn't drill mine and I'm getting real tired of having to fix the siphon on my HOB overflow all the time. Plus then I wouldn't have to have these big seios in my tank moving the water around.
Glaspie69 has drilled a few tanks and so has waverz both of them are close and could give you some pointers i'm sure. Just make sure the tank isn't tempered before you drill! Are you going to use the 55 as a sump?
I use a mag 12 as a return pump (sumbersed, not external) I don't really have any complaints about it. It's way too big for what I need and I have to keep it throttled way back. The eheim's are supposed to be awesome pumps though, can't even tell they're running.
I personally would get a pump that's made to run external to use on a closed loop that way it has a fan to cool the motor down and you don't put all the heat into the tank.
If you need help moving anything around or something just hollar!
musty baby
New member
waverz
Slave to the reef!
I agree, drill that sucker!! The only real problem when drilling tanks is heat. If you just keep cold water running over the area you are drilling you will be fine. Be sure to make sure your tank isnt tempered, then you will be good to go. I would take Jason up on his offer and practice on the 20, once you get that drilled its a no brainer.
CoralFiend
New member
I'm not from Iowa, but I recommend drilling it also! 
You don't have to drill your tank up like swiss cheese to have a closed loop. Drill at least one hole to feed your pump (preferably external) and you can go over the side with pvc or return from the edges of the tank. Be certain your tank does not have a tempered bottom, if you plan to drill there.
You don't have to drill your tank up like swiss cheese to have a closed loop. Drill at least one hole to feed your pump (preferably external) and you can go over the side with pvc or return from the edges of the tank. Be certain your tank does not have a tempered bottom, if you plan to drill there.
Thanks for all the advise. Ill be picking the tank up on Sun. I ordered and already have a hole saw set off e-bay and Ive got a Dewalt 18V that should handle things nicely. All i really have to do now is figure out hole placement. Im thinking one hole for the intake then one comming back into the tank. Kind of thinking of making a spray bar kind of loop to have multiple water outlets to keep the rock work clean. Or should i have two different return holes. Should I put the intake in the middle or the sides, same with returns? Any ideas?
Josh
Josh
CoralFiend
New member
The bits you got on e-bay are probably fine, but you may not be able to drill more than 5-6 holes before they wear out. Since you probably have never done this before, I would drill a couple of practice holes on some scrap pieces of glass first.
I would make sure I used a variable speed drill and go slowly. The idea is to wear through the glass, not drill through it quickly. Also make sure you keep the bit and glass wet while drilling, to keep the temperature down.
It would help if you could make a template to use to keep the drill bit in place while you start to drill and keep it from skating across the glass. Take a piece of scrap wood and drill a hole the same size as your glass bit. If you want, take some plumbers putty and put a thin layer around the bottom of the template, so it will hold water. Then hold your drill perpendicular to the glass and drill slowly. It might take you 10-15 minutes to wear through the glass, depending on the thickness. Don't rush it.
I would make sure I used a variable speed drill and go slowly. The idea is to wear through the glass, not drill through it quickly. Also make sure you keep the bit and glass wet while drilling, to keep the temperature down.
It would help if you could make a template to use to keep the drill bit in place while you start to drill and keep it from skating across the glass. Take a piece of scrap wood and drill a hole the same size as your glass bit. If you want, take some plumbers putty and put a thin layer around the bottom of the template, so it will hold water. Then hold your drill perpendicular to the glass and drill slowly. It might take you 10-15 minutes to wear through the glass, depending on the thickness. Don't rush it.
Satori
Cancer Sucks
I've drilled holes both ways; with a dremel and with the eBay hole saws. I say hole saws all the way.
The dremel took about an hour but the hole saw took about 5 minutes.
CoralFiend is right, the hole saw walks around a lot while you're getting started. I only did two holes with it, so I didn't figure out a way to keep it steady. In my case it didn't really matter, the hole placement wasn't critical, and the bulkhead covered the scratch marks. The holes ended being like 1/4" off from where I intended.
And keep it wet. I drilled on a slow speed for only about 5 seconds at a time, then stopped and poured a little water on it.
Also important: put a towel or something underneath to catch the big falling piece of glass once the hole is complete so you don't crack the opposite end of the tank.
The dremel took about an hour but the hole saw took about 5 minutes.
CoralFiend is right, the hole saw walks around a lot while you're getting started. I only did two holes with it, so I didn't figure out a way to keep it steady. In my case it didn't really matter, the hole placement wasn't critical, and the bulkhead covered the scratch marks. The holes ended being like 1/4" off from where I intended.
And keep it wet. I drilled on a slow speed for only about 5 seconds at a time, then stopped and poured a little water on it.
Also important: put a towel or something underneath to catch the big falling piece of glass once the hole is complete so you don't crack the opposite end of the tank.
CoralFiend
New member
I always cover the backside of the spot where I am drilling with several layers of duct tape. This keeps the plug in place and helps contains any water & debris.
Here are some pics of the way I drill, which is old school, but works well - if you have a glass drill. I got this drill from a LFS that went out of buisness years ago. It is essentially a portable drill press with a suction cup on the bottom. I have drilled dozens of holes with it over the years. These drills also work well with the diamond bits, but I use the metal tubing bits and silicon carbide grain. The bits are just hollow brass tubes. You build a dam and fill with water and a teaspoon or two of the silicon carbide grain. I drill on slow speed and the brass bit and carbide grain wears through the glass. May be old school, but it makes a very smooth hole. For someone in business who drills a lot of holes or a local reef club that wants to chip in to buy one of these, this is the way to go. I believe you can get them nowadays for around $400 new.
