I bought a couple of 40l buckets for £3 each from Asda to speed up water changes.
First I syphon water out of my 180l tank using gravel cleaner into a yellow 40l bucket. Use a yellow bucket so you can easily see anything you shouldn't have syphoned out, eg fish !!!
I then pump this water onto front lawn, via window, using a JBL 750 pump and short length of hose. I empty half the tank this way. Also fill a standard bucket whilst at it to rinse sponges, filters etc.
In the kitchen I fill two other 40l buckets with cold water, hot kettle water and dechlorinator and use the pump to pump it into the tank via a length of hose pipe. I have to do this as my hot water supply is ion exchange water softened and not suitable for fish tanks. The pump in the kitchen is on a radio controlled socket so I can turn the pumping off when tank is full. Also pumps quicker if buckets are on a work top rather then the floor as less differential height to pump.
Recently I have taken to using cold water straight from the kitchen cold tap as it makes water changes even quicker. Tank temp drops from 26 odd to 20 odd, but fish don't seem bothered, so will probably carry on this way.