8x6x4

[Yanos]

I’m planning my dream build of 8’x6’x4’ high.
After reading few builds here, I’ve decided to go plywood route.
Is the tank of above sizes doable?
Will it be safe?
What sort of ply should I use?
All the plywood gurus, please help

 

[AlexG]

Having built a couple of plywood tanks the 8'Lx6'W is doable but, the 4' high would be concerning. The primary reason I kept my large plywood tank to 3' tall was the number of failures that I read about when tanks went over this height. It is possible to go to 4' tall but the water pressure starts to get really high and the amount of bracing required is high. On monster fish keepers there was a shark tank someone made and I believe that it was built using lots of heavy bracing. Also I linked the thread for a 3000 gallon tank on R2R below that is over 4' tall. The other concern becomes the viewing panel at 4' tall which can use 3/4" tempered glass or acrylic of the correct thickness. If you go acrylic then I would look up some of the successful seals to acrylic to other materials (3000 gallon tank on this forum that has done a really good job of showing the method they used 3000 indoor/outdoor). There have also been a few failures of acrylic seals documented on R2R that have failed. Something else to consider with your tank height is the access to the tank which is a critical aspect for some aquariums. Best thing to do is take your time and do lots of research on successful tanks along with failures. As for the safety factor of plywood tanks if they are built correctly they can last just as long or even longer than glass or acrylic aquariums. I recommend a lengthy testing period when you get to filling as it might show flaws in a design. As an example my 720 gallon plywood tank started to bow on a test fill and required the tank to be drained so extra bracing could be added to the structure. On a second test fill the added bracing resolved the bowing issue.

For plywood I have used birch for tanks that will be getting a coating of pond armor. I have also used standard pine plywood for my first pond liner tank. I am in the process of building a second larger pond liner tank which will also use standard plywood for an interior rather than a nicer grade of plywood.

Feel free to ask away on the questions as there are a few other plywood tank builders on the site that can have some valuable input.

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[dantimdad]

Agreed. I have built dozens of plywood tanks and over a hundred glass. Don't go over 36" preferrably 32".

If for no other reason maintenance becomes a nightmare.

There is also the expense and complexity of construction.

 

[dantimdad]

Having said the above, an 8x6 foot print would pretty much guarantee you could keep anything you wanted and would be stunning if viewable from two sides or a side and an end.

 

[Yanos]

Guys, thank you very much for your advise. I knew that the height of this build will be a problem.
The largest sheets of ply I can get, are 8’x4’
I was thinking to build double thickness walls and bottom with two inch square timber to reinforce the joints.
As for a viewing panels, they would be 36” high with overlay eight inch top and bottom. I guess 3/4 glass panel will do. As for top bracing I was thinking about two pieces of one inch ply joint on both ends and screwed together and maybe two bars in the middle to join bracing together.
@AlexG your build convinced me that I can do it myself. Loving your highly detailed build.

 

[Yanos]

Having said the above, an 8x6 foot print would pretty much guarantee you could keep anything you wanted and would be stunning if viewable from two sides or a side and an end.

That’s the idea my friend. I want big shoals of anthias and chromis, as well as slightly bigger fish.
Size of the tank, as for maintenance doesn’t bother me at all. I’m quite a diver lol. Most importantly I want my fish to be comfortable and feel “at home”.