These are pricey, but they are the best:
http://www.aquariumcleaner.com/products.html

Pay attention when you order, as they have pads for both glass and acrylic.


" Anyone any suggestions/tips on shifting these without scratching the
acrylic? I'm currently using a Kent pro scraper/mop but the scraper is
occasionally scratching the acrylic and the mop wont budge the diatoms!

tia,

Sky