My math is a bit rusty, Al, but according to these two sources that I googled up
12” tall tank requires 1/4” thick
24” tall tank requires 1/2” thick
So for 48” tall tank, 1” thick is good, isn’t it?
I tried digging up the link for acrylic thickness that Pharoah had a sticky on but the link in that thread is dead. There IS mention of 40" tall needing 1.5 thick though. I didn't dig through all the 10+ pages but I think he and and I are on the same page - wouldn't trust anything over 3' with 1" acrylic. 4' tall I'd be looking for 2".
I've had several tanks that I bought from reputable manufacturers that were filled, drained and sold because they bowed so bad. Clarity plus comes to mind as being a repeat offender. 30" tall from 1/2" bowed like crazy, never even filled it all the way. Never had any issues with any of my Tenecors bowing - all their 30" tall tanks are 3/4". No way would I expect acrylic only 1/4"thicker to handle another foot and a half of water.
No way shape or form am I saying the tank won't hold and last for years, but I would sure think that with hundreds of gallons of water one would really want to error on the side of overbuilt and clearly 1" for 4' tall is far from overbuilt. I'd consider it under, but I'm not a reputable manufacturer either. Maybe I'm mislead and there ARE name brand reputable manufacturers straying that far from what I'd consider fair guidelines?
