I have a glass 29g that needs to be resealed. It doesn't have a center brace, but does it need the black rim to prevent it from bowing when filled? I just recently drained the tank and noticed that the bottom rim is cracked and was easy to peel away, pretty much providing no support at all. The tank has been filled like this for about a year now and doesn't show the slightest sign of bowing... do you think it'd be safe to reseal it and set it up rimless?