Acrylic Height Shortening Question

[vandy]

Has anyone ever chopped the top off their acrylic tank to reduce the height?

I currently have a freshwater 8'x3'x3' acrylic tank, and i'm looking to convert this into a frag tank. Would probably cut it down to 16".

Would putting a chalk line around the entire thing and taking a circular saw to it work? Can't seem to find many threads about this online.

Thanks for any help!

 

[D.WhiteShark]

Does the tank currently have any supports on the top? The first thing that I would consider if it did is, whether or not the sides would bow without support.. Can you share a picture of the current set-up?

also if you know the thickness of the acrylic. someone may be able to chime in from an engineering perspective.

 

[vandy]

Does the tank currently have any supports on the top? The first thing that I would consider if it did is, whether or not the sides would bow without support.. Can you share a picture of the current set-up?

also if you know the thickness of the acrylic. someone may be able to chime in from an engineering perspective.

It's 3/4" and it does have a steel top brace, but I can definitely source some acrylic to make a new eurobrace or something

 

[vandy]

Pics for reference

 

[D.WhiteShark]

At 8 feet long, I would definitely reinforce the top with some kind of brace. Could you reuse the brace that is on it now? In theory, if it holds it now, it could hold it @16" tall. Be sure to get a specialized blade for acrylic. As it heats up it tends to melt and creates issues with cutting.

FYI, that is going to be a killer frag tank! We are going to need progression pics of the project.

 

[X-37B]

You could build some 18-20" high frag racks. I could see several different levels.
Just a thought.

 

[Johnd651]

You could build some 18-20" high frag racks. I could see several different levels.
Just a thought.

agree... that extra water volume is huge.

But I had retrofitted an acrylic tank about 15 years ago. It can be done, but you will need to add back top supports. I over built it, and solvent welded in corners and eurobrace. Also if you can clamp down a cutting guide, vs using a chalk line, it will be a much better cut. Use a torch to polish the edges for sovlent welding.

 

[vandy]

agree... that extra water volume is huge.

But I had retrofitted an acrylic tank about 15 years ago. It can be done, but you will need to add back top supports. I over built it, and solvent welded in corners and eurobrace. Also if you can clamp down a cutting guide, vs using a chalk line, it will be a much better cut. Use a torch to polish the edges for sovlent welding.

Was it worth the squeeze?

 

[vandy]

You could build some 18-20" high frag racks. I could see several different levels.
Just a thought.

Thats a great point, but I'm more interested in feasibility to manage the tank. Even with a 10" stand, a 3' high tank still isn't easy to pull coral in and out. Appreciate the comment though!

 

[Johnd651]

Was it worth the squeeze?

No. The only reason I did it was because I was using coral for my grad research, and wanted a massive "sump" but it had to fit in a very specific spot in a university building. If it was at home, I would have not done it.