If they were falling off the wall they wouldn't sell them? Hah! Like they wouldn't sell goldfish bowls if they kill the fish due to ammonia poisoning? And they wouldn't sell cigarettes if they killed people? And they wouldn't sell bongs if the majority of people buying them used them for illegal drugs instead of tobacco?
Trust me, businesses aren't looking out for consumers about 99.9% of the time, or half of the things on the market out there wouldn't exist. It just needs to work for enough people for enough time that they can pass it off as saleable, and since most people don't care if a betta jumps to its death or dies in a drafty room from the inadequate temperature, most people will think the product "works" regardless of how many fish they have to replace. Remember, this is portraying fish as decorations, so the people who buy the product are likely to have a similar mentality.
While a well placed nail, perhaps re-inforced with some putty to make sure it sticks, would probably keep it in place, if you use an existing nail, you had better hope it isn't at all loose if you're going to put 8lbs of water, plus however much weight in gravel and ornaments, on your wall. I've had little 1/2 pound picture frames fall off walls at random because the nail simply got loose over the years from something hanging on it for so long. I'd imagine this would go even faster with a heavier object, especially one you probably have to keep hooking and unhooking for cleaning.
much better and more aesthetically pleasing in my eye
(tho, i would make sure it's mounted to the wall well so there's no accidents)
THAT WOULD BE COOL B)
