What water supply requirements does the K3000SE brewer have?

The brewer is designed to handle local water pressures from 40 psig up to 125 psig. Keurig requires the use of an external water filter such as the Omnipure KQ8A Water Filter (part number 5572), and failure to use a filter invalidates the brewer warranty. For the best tasting gourmet coffee, Keurig requires the use of filtered water in the brewer. (Pages 4, 6)