Splitting one tube to multiple

[OrangeGoldies]

Hi,

I'm new to fish keeping, so need some help. I'm running a Penn Plax Cascade 1200 on a 90G tank. I'd like to split the tubing so I can use two air rocks and a lily tube.

I don't know how to do it. Please be as specific as possible since I am so new this.

Also, does anyone know what size tubing the this canister uses? I can't seem to find the inside and outside diameters.

Thanks for your help!