When i filled up the water on my car the other day it needed refilling within 2 days?

When i filled up the water on my car the other day it needed refilling within 2 days?
If you park you car in the same spot ever day check under it to see if there any spot that are green (95 and earlier) or orange (95 -2008). Park in a clean spot and see if its actually leaking. then try pulling the oil dip stick and see if the oil on the stick is more of a yellow or white almost foamy looking substance. dis colored oil could mean you have a head gasket leak which is letting your oil and antifreeze mix together. on another note you should be using a 50/50 mixture (water /anti freeze) solution in your radiator. water alone will evaporate and cause you to refill more often. anti freaze temperatures can range from 170- 235 degrees. water boils at 212 degrees. hope this help.