Tap water comes out at all different levels of ppm. I've seen them come out under 100ppm and I've seen someone else's tap water come out at almost 500ppm. It's best, if your using tap water, to let it sit out for 24-48 hours before you use it. That will allow the chlorine and other tap water junk to evaporate off. Whatever your ppm is after a day or two of sitting should be low enough to work just fine.
With that (assuming you meant distilled water) water you should be fine. The amount is the key. At least double the pot size.