I put two Fluval 304 filters on my 75 gallon and love them so far. They are ultra quiet. Depending on the money you want to spend, you might want to check into the Hydor Inline Heaters. I put those on also and they work great. The water flows right through so you don't have to worry about where to position the heater to get water flowing past it.
Air pumps can be very noisy at times. If you use live plants, you may not need aeration as the plants will create quite a bit of oxygen. If you do get an air pump, check out the Rena pumps if they are available in England. They are also extremely quiet.