Easily remove oils & greases from swimming pool & hot tub filter cartridges. Up to 20 uses per bottle- add 50ml to every 1L of water- Just make sure your filter cartridge is fully submerged. Ensure your filter cartridges operate effectively, giving you clean & hygienic water. Extend the life of your cartridges so you can get the very best out of them & can replace them less often. Great way to prevent debris & grease build up which can lead to impaired performance. Easy to use with simple step-by-step instructions on bottle