Best Cloth Nappy Detergent?

Does anyone have any recommendations of their preferred brands of cloth nappy detergent? I've been using a brand called Charlie's which I've had to order online, but it's great as it doesn't clog the fibres of the nappy and ruin the absorbency.

It's kind of pricey, though - don't get me wrong, it works well, but I'd love to hear if anyone else has good brands that are cloth friendly and that may also be a bit friendlier on my budget! You know how it is as parents - money is better in my pocket than that of a big company! 😀