Horizontal, hang on back canister filter

Good morning,

I recently saw a video on youtube about how to make a horizontal, hang on back version of the canister filter and have latched onto this idea.



However recently it occurred to me that the weight of that on a rimless tank might be too much and chip/ crack the glass or even aid in pulling out the entire side.

I wanted to use it with a standard 3ft tank with glass of about 4 mm thick, is there a way that i can figure out what size will be too big for the tank to support it or will it just be better in general to add a brace of some sort to the back like a little shelf on what the filter can support itself

thanks