Cage help

Hello friends of r/gerbil I've had My little guy in the lower tank for a couple of months now and I wanted to give him an upgrade so I added the one that's higher up I know the tube's probably aren't the best way to connect them and I tried to make the as horizontal as possible cause I know they hate vertical tubing but I was wondering if anyone had any ideas on how to connect the tanks better my little guy hates tubing because I think he's colastriphobic.

As for why he's in fish tanks it's because I've tried every other cage types and I knew gerbils were chaotic but my little guy seems to have a bit more chaos locked into him cause he somehow managemanaged to chew through some of the metal bars in his last actual cage so I though a fish tank would do and it did the lower one is 55 gallons and and the higher one is 65

The second picture is one of him