I assume you mean in the cat's water dish or fountain?? I use bottled spring water or water that comes from a Pur water pitcher that has been filtered.The obvious answer would probably be filtered water I use that up super quick though (pur doesn't last long at all) wondering if tap would be super bad.
the sink attachments don't work on the faucet I have so I went with the pitcher.I think the sink attachment will help you out more cause it claims to do 100 gallons vs the pitcher only does 40. The only reason why I can't do bottled water is because I'm disabled with no car in the city so I don't see that happening. I thought my sink filters were supposed to last 3 months but it's only lasting like two. Or maybe that's normal. Idk. I can't even buy the filters on Amazon if I see it 5 bucks less on eBay I'll get that instead lol
You're lucky. We had well water here for a while and it was awful. It stunk.We live in the mountains of North Carolina so our well water is naturally pretty clean, but we use a brita faucet filter, it works wonders and makes things quick and easy. We also have a Pur water pitcher but to me it's a pain and my dad is really the only one that uses it.