The python faucet connector is the same thing as the ones for a water bed. Also if you can't use the connector on your faucet, you can fill the tank from the cold water side of a washing machine hook up. You'd still have to siphon to someplace else like a tub or a toilet to drain water though. There's a drain pipe under most washing machine faucets, but it's usually 3 to 4 feet up the wall, kinda high for a gravity siphon.
The next step of course is getting the RO
filter with it's own water tap. That's a whole different punch to the wallet though...