I water with tap, all I do is let it sit out for atleast 24hrs to get rid of the chlorine, no negative effects. dont even test ph at all, so you should be ok
That may work for you, but lots of places outside of major cities don't have the benefit of perfectly ph'd water straight from the tap, especially if they're running well water etc I'm in the same boat, but I know there are plenty of people that need to check this stuff. You'd think the OP would know the basic ph of whatever his standard water supply is...?
I'm not sure why people are saying it's perfectly ok to not check the pH of your water...pH is incredibly important for plants. Some cities' water is already at an ideal pH, but others are way off. I know mine comes out of the tap at around 7.9-8.1, which is much too high... Yes, pH is incredibly important if you want your grow to be the best it can be. What will eventually happen is certain nutrients will get locked out, and it might be a bitch to fix. It won't hurt this one time, but in the future, make sure your pH is ok. You might want to check the pH of your grow medium - now that you've watered with a higher pH (I'm assuming it's higher straight out of the tap - it usually is), you'll probably need to adjust it the next time you water. SO you'll have to water with a slightly lower pH than normal, to bring the pH of your grow medium back to a comfortable level.
one watering with an out of range PH water shouldn't cause too much trouble, it should be buffered by the soil. If you just go back to what you were doing from here on you should be fine. I have well water and it's way to hard and alkaline for my plants so I use rain water for mine.