[Kaosu]

i got an old 40 gallon for free on CL the people said they have had it for about 5 years..and they got it used....thick glass almost 1/2 inch lol....

my mother has a tank up that we have had for 13+ years now with out re sealing or anything....

so it just depends on the tank...whats been done to it, how it was made....and im thinking when..the newer tanks seem so flimsy .