Adaptor Required??

I'm rather appalled at the water quality in this country. The water from our taps are actually groundwater pumped out to a storage tank, that's located up on the roof of my house. I have a ceramic water filter which I want to have fixed onto my kitchen tap. But the fittings somehow does not match. I would have to purchase a suitable adaptor, or in the worst case purchase a totally new tap. I will hop over to Delta faucets to check out on their wide product range.