Old fresh water tank spout replacement help

Hi all, thanks so much for you feedback. In reading through your responses and in doing a little more research I’m thinking I may as well replace the tank and pump entirely. I’m going to such great lengths to make a beautiful interior that it would be a shame to have terrible water quality after all that!
I’m wondering though, on Amazon it seems that some of the water tanks specify that you should not hook them up to a hose... are there “special” kinds of tanks needed for being able to hook up to city water as well as just having a normal fill cap? I would like to be able to do both.
Thanks again in advance !