Can I use a Brita water pitcher instead of buying baby water for my five month old?

I was told in the hospital to use only spring water, not even baby water because babies that young don't need the flouride and it may cause flouridosis (discoloration of the teeth due to flouride consumption). My son is now 8 mo. old and every now and then I've run out of spring water so I used the Brita water. He's just fine. Plain tap water may have a bunch of stuff you don't want in your baby, but the carbon filter takes most of it out. I say use spring if you can, brita if you must, COLD tap water if you are desparate, and NEVER warm tap water as the heat draws out poisons in the metal of the pipes.