rimless

[ScubaSteve]

Then I say have at 'er but keep that rim intact while taking it off incase you find you need to put it back.

Get a box of razor blades from the hardware store (the kind you use for finishing, etc.) and get ready for some silicone fun. Don't bother with the silicone removers that they sell, they aren't worth it and they are full of chemicals that you wouldn't want making their way into your tank.

Slide the razor between the tank and the rim and slide between the silicone and the glass all the way around. You will probably have to do it a few times. Slowly pry the rim off without breaking it if you can. Once the rim is off use the razors the scrape away the film that the silicone leaves behind. You'll know what I mean, it'll be the stuff that is impossible to get off and will infuriate you. Keep using fresh blades and dedicate a few hours. That's it! Easy operation.

If you are worried about the sharp top edges you can finish them but be careful about scratching your glass.