Pets at Home currently have a clearance on many aquarium items. Usually rip off prices but some good deals to be had.
A few which I bought today.
The Interpet Goldfish Bowl Filter Starter Kit, which is on Amazon for £20, is showing as reduced from £10 to £5. This contains the small 60 ltr/hr .18 mbar APMini air pump which is on Amazon and EBay for £12 - £15.
Marina Micro LED lights in various colours for £1.88, Amazon price £7.77.
Fluval Ammonia Remover, 3 x 180g sachets for use with Fluval and other external filters for £2.38. Amazon price £7.62.
Lots of other bits and pieces.
Stocks will obviously vary by store but worth a look if you are close by.