it has a 1x2 frame on the outside for the glass to press against and hoping silicone to the liner to do the job of sealing it. unless someone has a better recommendation, that was my first idea to try. i am planning on 3 stingrays, some clown loaches, bala sharks?? not sure on what all is going in yet. yes it will be heated with 3 eheim 300w heaters in the sump. and it will be filtered through pillow fiber, then alot of bio balls, and returned with a pump capable of 3600gph.