Okay well first of all his tank was an acrylic tank, so there are some different rules that they apply to.. which I'll get into.
Okay if you really don't want to have a tank failure, one of the best things to do is to not have a massive tank! :funny: The larger the tank gets, the more pressure there is on the walls and joints. This is why you see most extremely large tanks built largely out of concrete, with only the main viewing panel made out of glass / acrylic (Usually acrylic). But still why do smaller tanks still sometimes fail?
That has to do with the seals. The most common way a tank fails is through the seal, particularly with glass aquariums since they are just pieces of glass wedged together and have silicone applied with a plastic wedge to keep everything straight and held together. Old tanks can have the silicone wear out over time, and a small leak develop , which if left untreated, can grow an eventually lead to the tank to fail completely. But usually the leak is spotted well in advance of a catastrophic failure, and you can make the necessary arrangements to get a new tank.
Acrylic tanks do not have silicone. Instead each molded piece is bonded to each other through a glue, and forms a very strong chemical bond which usually don't wear out. But sometimes they do from the sheets warping, but again a seal leak usually can be fixed quickly without a tank failure.
The worst way and most devastating way a tank can fail is a blow out. This is when too much pressure is applied on a pane, and the whole thing fails. When you get a tank, you will notice the edge around a glass tank include a large brace in the middle, or in the case of acrylic, its built into the tank itself. This is because when a tank is filled with water, the pressure of the water spreads out to the panes of glass, and pushes them out. You will notice a slight bow if you look parallel to a pane, but it would be much more without the brace on. If you notice a very large bow coming out, or cracks along the bracing, you need to replace the tank or frame immediately. Cracks can develop from the age of the tank, or things like the heat of Metal Halides weakening the materials, making them prone to give way to the pressure of the water.
You also need to make sure the thickness of the material can handle the tank. Most name brand tanks are well engineered and you shouldn't have to worry about it, but custom tanks must be carefully planned to make sure they are safe.
This is what I think happened to Peter's tank. The intense lighting, combined with poor engineering of a custom tank, and maybe poor quality construction, weakened the acrylic, causing it to give way to the enormous pressure of the water.
Don't let all of this discourage you though! tank failures are not very common, and can usually be prevented if you look for the signs.. cracks, water leaks, heavy bowing of glass / acrylic, etc. Also try to keep your rock work off the glass as this can increase pressure in specific points, and increase your chances of a failure. Try to spread out the weight by using PVC or other methods. to lift it off the glass.
Hope I have answered your question!
