Although I tend to do my weekly shop in Tescos, as we have recently had an Asda store built, I try to divide my shops between the two now as they are both similar in price, but it gives me a chance to try some new products at the same time.

I am quite religious when it comes to keeping my toilet clean and regularly use cistern blocks alongside a toilet cleaner as I believe they help keep the germs away.

However, I don't like spending money when it isn't needed and therefore I only purchase cheap cistern blocks. The cheapest cistern blocks in Asda are their smartprice cistern blocks and in a pack you get two blocks for the price of 30p which is rather a bargain as the better brands tend to charge around £1.00 for a pack so these are around 1/3 of the price of the better brands.

But, do they work? Well, obviously I can't see them actually killing the germs but I am confident in their ability to do this. You simply pop one into your cistern and within a few flushes the water starts to come through as a deep blue colour. Although the water changes colour with the block, it doesn't leave any colour residue around the pan and it makes your pan look really fresh. Even though the blocks are watered down by the time they enter your pan, you can still smell a real freshness from the block which is quite nice and makes your toilet seem really clean and fresh.

The coloured water makes the toilet seem really clean too and your pan has quite a shine to it after the water has been washed around the pan which says to me that these blocks do a good job of cleaning and disinfecting the pan.

The blocks are round and blue with a dissolvable casing to protect your hands from the block itself. I personally replace my blocks around once a month, but I would say if you religiously want a fully working block continuously then I would recommend that you replace it after 3 weeks maximum as by this time the water has faded to almost obscurity which indicates that the block has pretty much had it.

Overall these cistern blocks are cheap and do the job well. They leave your pan looking clean, smelling fresh and although I can't see they have killed the germs, I have enough confidence in the product to believe it has done this part of the job well. I will continue to use these in the future and they come with a recommendation from me.