180 gallon plywood tank

[AR1]

I want to build a 240 gallon (8 foot by 2 foot by 2 foot) tank with a front viewing panel. Now i have built a lot of large wooden structures, cages, etc, so i have some experience with wood. But here are a couple of questions.

First, how thick should the wood planks, used for the main structure, should be?
Second, is additional top bracing required?
Third, is there anyway besides pond armor or fiberglass, to make the tank waterproof?
And finally, how thick should the glass panel be, if tempered glass is being used?

wednesday13 Backfromthedead

 

[Backfromthedead]

Better off talking to jjohnwm or even Parka for a tank like this. Ive built one plywood tank that lasted several months so not extensive experience but i did learn a lot.

You'll want sanded 3/4" plywood for the walls and bottom. Yes, thats the pricy stuff. Im not sure what additional exterior framing you would need for an 8x2x2 but some kind of top brace would definitely be necessary.

Theres epoxy, liquid rubber, and fiberglass. Each with different advantages. It seems to me the most successful plywood builds incorporate all 3 of these into the design.

If it was me building this tank, i would probably just make a plywood box, apply fiberglass mat over all of the seams, layer of epoxy over that, layer of liquid rubber over that and the whole exterior of the tank. Some research would be needed to make sure everything would adhere though. Then i'd probably router some openings out of a 8x2 piece of plywood for the top, coated in the same liquid rubber on all surfaces.

 

[wednesday13]

jjohnwm has quite a few plywood builds under his belt…

I believe you can use 3/4” plywood with no extra bracing if u stay under 2’ height. Marine ply or reg ply… full top sheet with cutouts or top bracing is def. needed.

As for sealing it… fiberglass will always be the strongest but epoxy paint alone like pond armor can also stand the test of time. Many other products out there these days also. There is one used in europe alot thats like silicone u basically just trowel out over the entire surface… theres interseal 650 hs which is a proven paint used for bridges… plenty other pool paints out there and even drylock paint can work. Alot of rubber type paints also.

 

[AR1]

jjohnwm has quite a few plywood builds under his belt…

I believe you can use 3/4” plywood with no extra bracing if u stay under 2’ height. Marine ply or reg ply… full top sheet with cutouts or top bracing is def. needed.

As for sealing it… fiberglass will always be the strongest but epoxy paint alone like pond armor can also stand the test of time. Many other products out there these days also. There is one used in europe alot thats like silicone u basically just trowel out over the entire surface… theres interseal 650 hs which is a proven paint used for bridges… plenty other pool paints out there and even drylock paint can work. Alot of rubber type paints also.

TBH i fear his chiming in ,lol


I’m half expecting him to post something like, "You’re way over your head, kid!" or drop an extremely long article that’ll go right over my head, lol.

Jokes aside, I’m still searching for a good material for waterproofing. I’ve watched a lot of King of DIY’s build videos and read some of his threads here on MFK. They’re really useful!

Also, do you think buying a tank would be more ideal or making one? I was leaning towards making one since transporting and carrying such a big tank would cost me quite a bit, especially since the LFS is almost an hour’s drive away.

 

[troublesum]

I know Jack S*^t about building anything but it pretty easy to figure out costs for materials and labor vs just buying a tank maybe check out your local ads and buy a used one and reseal it if you have the time to build a tank from scratch i'm sure you have the time to reseal one

 

[Alexxxxsv14]

Just buy one lol 240 is pretty common check offer up

 

[AR1]

Just buy one lol 240 is pretty common check offer up

Will check local prices here.