The children won a goldfish at a fair last year and to my utter astonishment it is still alive. At first it lived in a small tank that my husband had when he was growing up which was easy to clean, but as it got bigger I had to upgrade it to a bigger home. My lovely sister in law gave me hers and it's amazing but it's massive (the fish loves it!) and I used to absolutely dread cleaning it out: an afternoon of ladling all the water out with a jug, then scrubbing off the algae before filling it up again. Since I discovered these two pieces of equipment it's a breeze, well almost!
* A vacuum water pump £1.50 from Amazon which displaces the water. Simply put one end into your tank and the other into your sink, squeeze the pump a couple of times to create a vacuum which draws the water out of the tank. Once it's set up you can leave it and get on with something else... genius and the kids are mesmerised by it! (Alternatively you could suck on a piece of tubing to get the displacement going, though I didn't fancy risking dirty goldfish water in my mouth!)
* A magnetic algae scraper. Simply put one side of the magnetic brush on in the inside of the tank and the other on the outside and move them around! No more scrubbing, what's more the kids can help! Again can be bought from Amazon for £2.99
I wouldn't say I now look forward to cleaning out the tank, but I certainly dread it less!