HI, I visit Guayaquil each year and visit other cities also. What I’ve learned to do when visiting private homes / family is to put 1 cup of Bleach into their water tank each place I go the moment I get there. If I stay more than 2 days I put a 1/2 cup each day into the water tank. I let the water run for a day to clean the pipes, then I use it and have no problems. Bleach kills all the germs.