Generally the water purifiers fit most standard faucets but for your info most of the people in Qatar do not drink the water from the tap even purified (desalinated water + old pipes + questionable cleanliness of water tanks + high temperatures ideal for bacteria development).
The best solution is to invest in a water cooler (around 400QR) to have at any time pure and fresh water to drink (some people even recommend to use bottle water for cooking).
All the supermarkets are delivering the bottles (8 to 10 QR for 5 gallons-19L bottle) needed for water cooler (different brands available).
Generally the water purifiers fit most standard faucets but for your info most of the people in Qatar do not drink the water from the tap even purified (desalinated water + old pipes + questionable cleanliness of water tanks + high temperatures ideal for bacteria development).
The best solution is to invest in a water cooler (around 400QR) to have at any time pure and fresh water to drink (some people even recommend to use bottle water for cooking).
All the supermarkets are delivering the bottles (8 to 10 QR for 5 gallons-19L bottle) needed for water cooler (different brands available).
Check this QL users discussion about tap water : http://www.qatarliving.com/node/111603