This point also varies by manufacturer. I bought a Perfecto tank and stand combo, 55gal. I was looking under the stand the other day, the tank is actually held up by the ends. There is no support under the long sides of the tank, just two 12" lips in the stand that the tank sits on. And this is a stand designed/made by the same company that makes the tank.Fact. aquarium manufactures recommend stand be made of solid wood with flat strong supported surfaces to support the entire bottom glass as most new decorative framing is only 1/32 inch thick on the bottom. Perimeter support is not recommended.
Yup your right, the reliability factor goes up from like 1.8 to 3.6.Tempered is a lot stronger, it will not chip or crack. As stated, if it takes enough abuse, it will crumble. It will completely shatter, into thousands of little pebble like peices (that are NOT sharp). Standard glass can also shatter. It will crack or chip first. If it is strained enough, it will shatter, and the pieces will be sharp. This shatter point is lower than the shatter point of tempered glass. The only advantage of non tempered glass is that it can be cut.
Like any material, Glass (tempered or not) can take a certain amount of strain per area. It is cheaper to use this to your advantage. It is more reliable to not. A solid supporting surface will provide better reliability in that it 'backs up' the strength of the glass.
I saw this thread and felt I had to reply. There is some correct information and some incorrect.My long awaited questions has been answered by professional factory aquarium builders.
Fact. the decorative trim on the aquarium has no benefit whatsoever in strength or structure but invented purely as a manufacturing aid to hold the panels in place during the gluing process. It is the silicone that does all the supporting between the panels not the decorative or assembling plastic framing. If you took it off it would make absolutely no difference other then to hold new panels in place for the gluing process.
Fact. Added bracing comes in the form of the center top glass strap where aquariums are longer then 48 inches and hold more then 100 gallons. The alternative is Euro bracing.
Fact. The bottom glass in manufacturing is never tempered unless special ordered due to its catastrophic failure nature (explodes when fails). Non-tempered is used because when it fails it cracks and the leak is usually a controlled spill.
Fact. The cutoff between using the "capped method" of bottom glass placement (all side panels sit on perimeter of of bottom glass) or "free floating method" (bottom glass is recessed inside and even with all 4 vertical panels) is when 1 inch glass is used.
Because of the sheer weight of 1" or larger glass vertical panels and the amounts of water they designed to hold would be too much weight to be sitting on top of the perimeter of the bottom glass using the "capped method", the "free floating method" is use instead which is a more difficult assembly process but no more stronger then the "capped method" in so far as bonding strength is concerned.
Fact. aquarium manufactures recommend stand be made of solid wood with flat strong supported surfaces to support the entire bottom glass as most new decorative framing is only 1/32 inch thick on the bottom. Perimeter support is not recommended.
*Incidentally, please do not construed this posting as any kind of slam on opinions we have all given including myself and which have help greatly in perusing the whole answer. These particular and crucial questions I sought out from the factory so that they would help us all have a solid foundation as to WHY these method are used and preferred by manufacturers.