I have a Bengal cat myself. He consistently jumps 6-7 feet in the air do get onto my TV, dressers, countertops, etc. so the fish tank at 4.5-5 feet was easy for him. I have shooed him off a few times, and used my classic line, "Not for kitties..." I used to wake up, when I had my glass tops, and find wet paw prints dried on the front glass from where he would dip his paws in the water in the back where there was a small opening, and rub it all over the front glass.
I never knew how to stop him, but I got to the point that the sound was so ingrained into my mind, that I would actually wake up from sleeping if he jumped up there.
Furthermore, I have since added a screen top and ditched the glass tops altogether and so far, other than having a few actual nightmares of him jumping up, falling through and drowning, I haven't had any issue.
I just hung my Radion on the tank and now I'm waiting to come out and see him using it as a swing!
Good luck to YOU!