Just picked up a new to me 90 rimless. I got a deal on it but it was dry when I picked it up. The guy I bought it from said he had it running for about 2 years and it’s been dry for ~1 year. My buddy brought up that he hasn’t seen any large rimless tanks with “standard sizes” (48”x18”x24” LxWxH) and the tank has a plastic rim around the bottom leading him to believe it may have been a rimmed tank at one point. I asked the seller and he said it’s a custom tank by a shop that used to make tanks in Daytona FL (that’s where I bought it) The glass is 3/8 or 10mm. It looks as if it was resealed at one point. I’m just trying to make sure it’s safe to fill up without falling apart. I didn’t have any doubts until my buddy started asking questions. I don’t have any reason to doubt the seller he is moving and looking to downsize, super nice guy and very upfront about everything.