120 gallone plywood tank

[toddjarow]

Hi. I am getting ready to design and build a 120 plywood tank. It is going to be 48" long x 24" wide x 24" high. The only question it how thick should the plate glass be?

[lohachata]

all you will need is 1/4" glass...i have built many of these tanks over the years.larger ones also...a 240 gallon tank measures 24 x 24 x 96 and only requires 1/2" glass...
a friend of mine gave me an old 150..the bottom is cracked so i have plans to build 2 327 or 392 gallon tanks and a couple 90 gallons from the end pieces.

[toddjarow]

Are you sure that won't break under the water pressure? Also, any ideas on what I can use to coat the wood? I am having a hard time finding epoxy anywhere. Will the epoxy used on garage floors work?

[Sea-Agg2009]

1/4" is what they use for nearly all home aquariums. You get the idea from this month's FaMA?

[lohachata]

back in the 60's and early 70's we used Pratt & Lambert "Pal Guard" 2 part epoxy paint..then many of us switched to Sherwin Williams "Tile Clad II" also a 2 part epoxy...i also like to use the S&W "Polane B" as it has some very desirable properties.when properly applied , it can eliminate the need to caulk all of the seams with silicone.
i also suggest a 2x4 across the front and back of the tank to eliminate and bow....

1/4" glass is plenty thick enough..i have seen 200 gallon plywood tanks with 1/4" glass...

when you go to cut the front window ; draw the window outline.. then find a 2 lb coffee can and place it at the corner on the inside of the outline... place it so the edges of the can touch each side of the outline.. then draw an arc around the can..
this will give you rounded corners on the window and will result in a stronger framing...
when running the bead to set the glass onto ; do not run it in a straight line..... run a zigzag line around the perimeter ; then run a straight line down the center of that....then place the glass...