Drilling a sump that is in use?

[Swimboy123]

Hey all;

I'm getting to the end of my new build-out (thank god!) and my plans have changed a bit from start to finish. I have a 45g tank that has been up and running for the past 8 months or so. It's plumbed into a 90g sump that will also facilitate my 150g main display. The quadrant of the sump where the return pump intake will be can be drained while the rest of the sump is still filled. My question is, is this a good idea? I've drilled plenty of acrylic before but all of them have dry. I didn't know if the weight of the water would somehow change of fluctuate the pressure that is distributed though the entire sump structure, and if so, would the penetration of a bit split (or somehow torque) the acrylic. Does anyone have any experience with this? Any advice would be greatly appreciated.

[FearTheTerps]

If it was glass I would say no way, drain it. With acrylic you may get away with it, I don't think I have ever heard of someone cracking or breaking their acrylic tank while drilling.

[Chad]

I don't think I would think twice before going for it unless your sump is very fragile (i.e., too thin to start), in which case you have other issues anyway. From a structural stadpoint, holes that are further than a diameter distance from the edge have minimal impact on the strength of the material... but even then I would still pull out the drill and go nuts.

[Swimboy123]

Thats kind of what I qas thinking as well. It is 3/8 or 1/2 inch so I was fairly sure I would be ok. Thanks for the responses. Anyone else?

[Origami]

As long as the partition that is holding the water back can withstand the load of the adjacent compartment's being empty while you drill it, I don't think you'll have a problem. Go with it.

[jason the filter freak]

Also make sure you have someone there to keep the bit wet, also make sure you have clean up stuff on hand (lots of towels and a shop vac, just in case.

 

and... triple check that the tank is not tempered, otherwise go for it!

[Origami]

... would the penetration of a bit split (or somehow torque) the acrylic.

Also make sure you have someone there to keep the bit wet, also make sure you have clean up stuff on hand (lots of towels and a shop vac, just in case.

 

and... triple check that the tank is not tempered, otherwise go for it!

The way I read his original post, the sump is acrylic.

[Swimboy123]

that is correct

[jason the filter freak]

Whoops I read the part where you said you drilled acrylic before (I thought you meant you had practice drilling but missed the part where the sump was acrylic. Take it really easy when you do it, make sure your bit doesn't bind, a dremel may be better than a hole bit. I would also still consider lubing the the drill site. Put something behind it so the lube doesn't get into the sump, and use something like canola oil.

[Origami]

Also, keep the speed of the bit / hole saw down. High speed tends to melt the acrylic and can bind the saw up quickly.

[Swimboy123]

ok, I'll keep you guys posted. Thanks!