Invest in larger storage tanks, barrels, or trash cans to store your water. Polyethylene tanks are the best imo. You can set up a pump with uni-seal gaskets on a loop to circulate it to age it, and keep the heat distributed evenly, and install a T fitting in the loop with some ball valves to connect a long vinyl hose to pump the water wherever you want. Install a ball valve on the end of the hose so you can shut the water off where your doing the water change, not run back to the storage tanks to shut it off.
-Leland