How can I install the electrical and plumbing for an aquarium filtration system through an exterior wall?
I don't claim to know California building code. That said:

I don't think the building code cares what you do with your aquarium piping, so long as it doesn't connect to your residential plumbing. Do what you want with that top-off tube.

As for electrical, if you want to run wire then it's a bigger deal and there are lots of rules you'll need to follow. Too many to list here.

Essentially, you'll be looking to install an outdoor outlet that you can plug your pump into (If you try to permanent wire it, then even more rules will apply).