I once used pop bottles to make a run out one side of a cage and into the other.LOL
I cut the bottoms and tops out and taped them together.
Not a good idea for connecting them though.
If the tubes your are refering to are the hard plastic they should be fine. I like those because you can see through them.
You can always use ABS pipe, most chins can't/don't chew them much.
I use heavy crafters wire to wire items on cages, that might help attach the tubing.
Just some thoughts