if i owned a home rather than renting an apartment then i would create a system integrated with the home plumbing system to allow for easy water exchange. i currently have a system in place right now that is quite convenient, however the holding tank is very small because of limited space. i can understand how the minor fluctuations in temp and very brief exposure to chlorine is probably not that harmful to my fish, but this is actually the first time i've had a very stable tank with extremely healthy fish and i'm quite nervous about screwing that up. so you guys are honestly saying, get the tap water close to temp by feeling it, dump prime in the tank at the amount required for the given aquarium total volume, and fill it with a hose? that surely would be quite easy. now do me a favor, figure out how to do that for my reef aquarium.. :-)