I like the looks of the one from Forster. my Himalayan has crystals and is already on the prescription cat food. I live where the closest vet is over 300 miles away and it costs a lot to take fur baby there ( my ticket, not hers) . I travel for the job and am gone 3 days out of the week. my cat sitter does not come in and change the water the two times a day Miss kitty likes so this will help her keep the drinking up. we just did super expensive bladder surgery for a bladder stone;i would rather pay for a water fountain than repeat that procedure. she also like running toilets so this is definitely worth a try.