Drilling a Filled Tank...

[Dewman]

O.K. That was just to grab your attention.

But seriously, I want to take the skimmer off the back of my 29 gallon (hang on sump and surface skimmer), but I don't want to drain the tank and drill it. The reason I want to do this is I want to increase the useable space in my tank. I don't know the first thing about how to get water down to the sump and then how to get it back up to the tank. I assume I will need a pump to get it back up, but can I use the syphon method for draining it down? How can I be sure that the pump I use will pump out fast/slow enough to keep the sump from overflowing or running dry . Also, what to do when the electricity goes out?
Any help would be great.

 

[Anonymous]

hi.
Did you consider the use of a over-the-tank overflows? Examples of them can be found in CPR's website: www.cprusa.com

 

[newkie]

I wouldn't go with CPR, but there are good u-tube overflows which are reliable and safe. Check out www.lifereef.com. CPR is junk.

 

[Dewman]

So I syphon the water down to the sump, then use a float switch on a sump pump to make sure the syphon doesn't overflow.
What would be a minimum size sump for a 29 gallon tank? I thought a ten gallon would suffice?

Again, any help would be great.

 

[Dewman]

btt

 

[geofloors]

You use an external overflow box with that will siphon the water out at the same rate the pump returns it to the tank. You need to make sure the overflow box will handle the flow rate from the pump. If the pump is too small air bubbles will collect in the U tube and stop the siphon, in turn will cause a flood. If the pump is too big then the tank will flood also. When the pump is shut off there is no more water returning to the tank so the siphon will stop...when the pump is turned back on the siphon will start again. When the pump is turned off an equilebrium is reached between the inside and outside overflow boxes and it will keep water in the U tube for restart. I also agree that CPR overflows are no good. I have no idea about drilling a full tank but I wouldn't try it. If it cracks you'll have allot of water on the floor.

George

 

[NasotheHutt]

With an acrylic tank, it's possible! I've done it! Place a large mouth plastic cup on the inside of the tank where you plan to drill. Using a RotoZip drill a hole in the bottom of the prospective hole, let the water drain out into a bucket, then cut out your hole. Next, cover the outside with your hand, remove the cup from the inside of the tank, slip the bulkhead into the hole and cover the inside of the hole again with the cup or your hand. Having a friend holding the cup helps. Then dry and tighten the bulk head, and plumb in a ball valve. Your done!

HTH
Scott

 

[nin0]

U know the best overflow box is a hang on the back filter like the penguin biowheel for example. Just drill a hole the same size as the siphon tube below the filter compartment and you have yourself an overflow box that you dont have to worry about flooding because as the power goes out, the impeller turns off stopping the water from entering....also its not as noisy as an overflow box.....then whatever the flowrate of the biowheel filter is then the pump should be matched to that flowrate keeping in mind that flowrate of the pump decreases as it gets further from the tank. I havent actually done it myself hehe but am going to since i want a hassle/noise-free overflow. I dunno if it will actually work but just a thought.

 

[2poor2reef]

I don't think that would work nin0. But if you ever try it send us a pic. Anytime you use two pumps, in your case one to fill the biowheel and the other in the sump to return water to the tank, you have trouble matching flows, and one tank or the other will flood. But maybe I misunderstood your suggestion.