Details of my fishroom
Here I'm gonna try and show you what it takes for me to do a water change in my fishroom. 
Filtration System Inside the sump
The cities water is taken and drawn through my four filter system.  Carbon Filter, Ceramic Micron Filter, and two cotton filters.  In order to filter the water the valve to the right must be in the on position until the sump is full. Once the sump is full the float valve turns the water off.  However to make sure I turn it off at the valve before the filtration system.  The sump also has a overflow and a backflow to prevent too much pressure going through the tanks.  Keeps showers to a minimum :)
Valve Manifold
Water Pump
When I want to do a waterchange usually the sump is full of water.  So I just turn the ball valve to the bank of tanks I need to top off after cleaning them. 
Then I flick the switch for powering up the water pump.  The tanks fill and then I turn off the water pump (before the sump is empty of course).  It takes about 5 minutes to do the job. 
Pre-drilled tank with bulkhead Assemblies
Piping
The flow of water to each tank is regulated by these ball valves.  There is a ball valve on every tank.  There is also a drain pipe on every tank.  The drain pipe helps to keep the water from overflowing onto the floor.  The drain pipe can be directed to a level you want the tanks to drain to if you don't want them too full.  Granted its just a backup for those overflow problems common in fishrooms but hopefully youll catch it before it's too late cause its not totally foolproof if the tanks are filling too fast.
This is the plumbing behind the tanks.  There is supply and drain pipes here.  Pretty much explanatory :).