Yes, quite a few of us use duct tape. It doesn't hold underwater and if you're using it in really damp conditions, better check it frequently. I keep a role of black duct tape beside the tank so it can be changed out easily. Also, when I had my bimac, I kept a heavy brick on the tank cover as well.
Bricks are good!....There are many and varied ways to try (yes I said try) to keep an octi in the tank......duct tape, bricks, wet silicon, astroturf etc etc, but I think the best is a combination of bricks, duct tape and eternal vigilance!
My little guy shows no interest in escaping. I have never seen him above the top half of the tank. I have live rock stacked bottom to top in the tank so maybe there are enough places to explore. I have artificial turf around the sides of the canopy and leave the top open on the tank. As my guy grows larger I am sure I will have to take further steps to keep him in..
I am currently working on my tank top and making it octo proof.
I'll let you know how i get on and post some pics.
Perspex, perspex, perspex
i also wanna make some open bit on the top to enhance my gas exchange ( water only few mm off top of tank glass screen and minimal ventilation to sump) so tryin to avoid many difficulties in a major swoop!!!
also my inflow drops through this screen.......hhhhmmmm
thats complete jibberish what ive just wrote but am workin on it!!!!!