A 500 gallon all glass mega tank project

[CWO4GUNNER]

I recently have been looking over post of folks that have purchased mega tank sizes 500 to 700 gallons. In each case whether acrylic or glass most pay between $2000 and $4000 for just the naked tank! While I was impressed with the though of heaving a mega tank where enormous fish can be kept, I also realize that of spending that kind of money for any tank is just out of the question IMO.

Then suddenly it occurred to me that having rebuilt a 244 gallon tank from scratch a 500 or even 600 all glass tank would not be much more difficult especially from what I leaned about how to build stands from wood studs and wood jigs for glass panel replacement. Im thinking that I can factory order 1/2" glass for about $7 a square foot which means that all the panels and bracing for a 500 all glass tank will cost under $500 or roughly a dollar a gallon. Ideally his means that I can simply construct a rimless center-braced all glass tank using just silicone, glass and jig-framing without having to use the labor intensive method of plywood, resins, fiberglass, screws nor steel supports, and because its all rimless glass could be an Island display tank. Even though a finished aquarium (tank, stand, canopy, filtration, and contents) requires a bigger investment, being able to DIY build the naked tank for 80% $500 or $2000 under retail of what others pay ($2500) with shipping. Its a great idea and amazing savings.

As some of you have noticed I have been selling off my smaller tanks under 150 gallons (God willing) in preparation for a DIY all glass mega tank built on site where it will sit on its stand, the lip of the stand acting as the bottom jig. When? Soon I hope, selling off a couple more tanks and making room will will be pivotal to when I start and quickly finish. When I start I will bump this thread

 

[mott]

Sounds like an awesome project, what kind of fish are you planning? It would be a great low tech planted tank, I wish I had the room for something like that!
Awaiting the outcome

 

[The Zigman]

MOst tanks I have seen larger than my 125 were thicker than 1/2" (my 125 is 1/2" and bows considerably)

I would also price out thicker glass, depending on the depth of your project, just to be sure.
I have an idea in my head for a 400 gal tank with a stainless steel frame, so I will be watching your progress on this.

 

[CWO4GUNNER]

Glasscages.com the cheapest online seller, sells there standard green glass, no overflows, 96L x 48D x 25T by 1/2 inch thick all glass tank with center brace for $2669 plus $480 shipping. Its the column of water height that is the key to glass thickness because water column height determines PSI not volume. My 244 tank is 30 inches tall and 72 inches long and uses 1/2" glass mostly because of height and has absolutely no bowing at all, partly because it properly center braced at the top.

The linked table below shows aquarium glass thickness requirements and it is base on only 2 factors water column height (tank height) due to water PSI and tank length since the length of a rectangular aquarium has the longest span and therefore like a bridge has most leveraged force placed upon it. The ends or width is not a factor as long as they are shorter then the length. So as you can see below a tank that is 24" high by 96" long can easily be made of 1/2" or 12mm glass with a safety margin of 3.46. If your tank bows it is not braced properly at the top.
http://saltaquarium.about.com/od/planasystem/ig/Guide-Charts--Tables--Diagrams/Glass-Thickness-Calculator.htm

NO bowing, this tank is my 244 and would only need to be 2x wide to be 488 and would still not bow with 1/2" glass because the height & length would not have changed

 

[CWO4GUNNER]

PROJECT PLAN CHANGE 1

As you can imagine from just an idea a project like this requires structural and financial research based on current trends, while at the sane time trying to find better ways to save on labor, weight, and cost of materials. I my be a bit single minded at times in order to see a task trough, but I was also trained to be objective toward needed changes in order to have a more effective plan. In simple 1 line terms the following will be made to my plans:

(1) Since the price of even 1/2" glass has gone up considerably I have decided to build a single glass front viewing panel tank.
(2) Although plywood is cheaper to build the remaining 4 sided wood support box tank for the main front glass viewing panel, wood stud framing materials are excessive, expensive, and labor intensive.
(3) Where my tank will be different simpler and lighter when assembled and far easier to disassemble if transported will be that I will use steel angle-iron welded framing in the outside cornering and center supports of a water proofed 7/8" oak plywood box. This will provide a stronger, less bulkier, thinner walled tank, and perhaps even lighter sine all the vertical wood studding will be eliminated on all 5 sides of that tank.
(4) the size of the tank will now be dictated by the standard sizing of plywood paneling to eliminate the amount of custom cutting and sizing. The tank size will simply be 8 feet long by 4 feet tall by 4 feet deep, as a result the tank will approach approximately 1000 gallons.
These are my changes so far as I build this plan, there of course be more changes as I research and build this thing in my head going through many failure scenarios and eliminating each one.

 

[dbosman]

Monster Fish Keepers has lots of information about large tanks, and most of the accurate information on the web, about DIY large tanks.

You will want to purchase your plywood from a lumber shop. The difference in strength between, just for instance nine layer 1/2" plywood, and five layer plywood is incredible.

 

[CWO4GUNNER]

Agreed and Im am looking at allot of fabrication types and methods. But because I happen to weld, have a welder and allot of stock sitting< I am set on a plywood steel-frame tank. And yes many of the new finished grade 7/8" thick hardwood plywood's are 8 to 10 multi -layers sold at Home Depot and lowes either in Birch or Oak, no way Ill use pine. But I will check out the lumber yard selections as well and have everything pre-cut. The great thing about using steel is that it can be pre-load stressed when assembled over the plywood box unlike using studs which are at ambient stress when assembled, my steel framing and supports will be tightly under load before the tank is even filled like an oak wine drum where the steel bands are heated when placed on to shrink, my steel support will be stretched into place then welded.