aluminum aquarium???

[spearfish]

hi from the swamps of Louisiana,
I was wondering if anyone has ever heard of a tank made out of aluminum? :?:
I want to make an xxlarge tank 8'Lx2.5'Tx3'D=448gal. Since i work at a shipyard i have access to large sheets of aluminum at a very cheap price.
It would be built more or less like a plywood tank but with 1/4" thick aluminum plate for the back,btm,sides insted of plywood. Inside would be painted (2-part epoxy) then lined with black formica glued and sealed with silicone. Front pane is to be 3/4" Lexan.
Any comments would be greatly appreciated.

 

[Acrylics]

hi from the swamps of Louisiana,
I was wondering if anyone has ever heard of a tank made out of aluminum? :?:
I want to make an xxlarge tank 8'Lx2.5'Tx3'D=448gal. Since i work at a shipyard i have access to large sheets of aluminum at a very cheap price.
It would be built more or less like a plywood tank but with 1/4" thick aluminum plate for the back,btm,sides insted of plywood. Inside would be painted (2-part epoxy) then lined with black formica glued and sealed with silicone. Front pane is to be 3/4" Lexan.
Any comments would be greatly appreciated.

I can't comment on the aluminum though I'd imagine it should be okay. I would strongly suggest you not use the Lexan though for a variety of reasons - the main one being that if you think acrylic scratches easily - Lexan is far far worse. Stick with acrylic or glass for the viewing window.

James

 

[Anonymous]

I heard that Lexan also bows more than acrylic, because it is a softer plastic, it that true?

 

[spearfish]

i should have been more specfic in regards to my material specification....i plan on using G.E. Lexan Margard (abrasion resistant coating)....i cant comment on acrylic vs. polycarbonate when it comes to bowing as i have not looked up the mechanical data on them yet. but i will before purchasing anything

 

[Acrylics]

i should have been more specfic in regards to my material specification....i plan on using G.E. Lexan Margard (abrasion resistant coating)....i cant comment on acrylic vs. polycarbonate when it comes to bowing as i have not looked up the mechanical data on them yet. but i will before purchasing anything

You especially don't want to use Margard MR-10 or anything with an abrasion resistant coating. Lexan is a much softer plastic, and will bow far more than acrylic and is also not nearly as clear - it has a pale gray color.
Margard brings up two more issues:
Because polycarbonate by nature will bow more - the hardcoat (abrasion resistant coating which essiantially a micro-thin glass coating) will crack (fast) and when it does it sluffs off in flakes which make the whole thing all that much more unattractive and defeats the purpose of using the coated material to begin with. The edges of the cracks and flakes will become havens for coralline algae and nearly impossible to clean off because they are in cracks now. You can't buff out any of this either because the coating will not blend in with the plastic itself - you're basically stuck with it.
Generally speaking Lexan does not glue well enough to give sustained pressure-tight joints over the long term, Margard does not help this by any means because the hardcoat is not only "Mar-Resistant" but also very chemically inert which means most solvents can't get through it and silicone pretty much won't stick at all. Couple this with the bowing issue and you'll see that there will be a lot of strain on this joint.
I understand the desire to use Lexan due to it's "unbreakability" but it simply is not suitable for aquarium panel use (IMO).

HTH,
James

 

[saltnmyeye]

what kind of silicone should one use to seal a tank like this and what kind of paint should be used and should acrylic be used for the viewing window and how thick say for a 90 gallon?

 

[Anonymous]

For 90 gal, I feel it is too much hassle to go with al. tank with acrylic front. but if you insist, a 3/4 inch thick acylic in most cases will be overkill already
(unless you want a tall tank higher than, say, 2.5 feet)