Bought a wee gadget today which is good for speedy water changes so thought I'd come and let people know about it in case they'd never seen one before.
Its called a drill pump and it is a pump which is powered by a drill, you just attach tubing onto the inlet and outlets then "drill" to pump the water in or out. It can pump up to 50 litres per minute so probably only useful for bigger tanks.
It made putting my fresh water in much easier as I either had to use a jug or a bucket before.
Here is the one I bought