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Octo-proofing a hex tank... ideas?


Aug 21, 2006
i need an idea on how to octo-proof a hex tank i'm setting up for an octopus... i'm either going with a dwarf or bimac, depending on what's available in my area...

what do you think?

i'm thinking some sort of screen rubber banded on the top of the hex... using an internal filter for carbon, or a fluval... i was going to build a rock "mountain" in the middle of the tank and put a powerhead or two behind that....

my main concern is the top of the tank.


Colossal Squid
Nov 19, 2002
Rubber bands probably won't work. Octopus are very strong for their size! Duct tape is good (if you don't mind the look!) also weight on the lid. Others have gone for the DIY option and have hinged the lid to the tank and used various external catches. Because our lids are out of view, we've always gone for the brick on the lid approach for small octopus, our big one has a sliding door arrangement from the top of the tank to the roof, which can be locked if necessary. BTW I work in a public aquarium, hence the out of view comment and the large scale doors!!!


Mar 21, 2007
what might work for you is what i did to my tank. buy a sheet of plexi-glass from lowes or home depot and find a way to cut it to exact measurement in my case i have a roto-zip which worked wonders! i even got fancy and cut out a whole section and placed hinges on the top so i can open and close it, i used Velcro to keep it down and its pretty tuff to pull, even for me. i have a 75g rectangle tank but im sure this would work to the same effect for your tank. (the roto zip even allows you to cut around tubes and filters. i have a fluval and a skimmer that i cut around and it makes for a perfect seal)
Jan 3, 2007
Cutting to fit a piece of plex or acryllic sounds like the most secure and aesthetic way to go.
If you dont have a saw then your local glass store will probubly be able to help you out. They can most likely do the whole thing for you.
If you want to do it yourself you can use poster board to make a template, then trace and cut....no problem.
Remember, you have to look at and live with your choice, so make it the best you can....An Octo deserves nothing but the very best.

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