That's nice! Good grow, bro!
If you are measuring distilled water with an electronic probe, you won't get accurate results. Those meters depend on some ion transfer to work, and there aint no ions in distilled water.
The pH doesn't even matter until you start adding nutes. All the plant needs up to that point is water and light. pH won't really have any effect on water takeup.
I agree with the other recommendations for the Apera pH pen. Nothing but good things to say about it. Cheaper ones I bought initially were pretty much junk. If you want to be extra safe, get a decent pH test strip kit. They are not terribly precise, but they will keep the electronic meter somewhat honest. Also they are great for testing water that is allegedly deionized. In that you can test your distilled water with those. It will never be a perfect 7.0 as dissolve co2 will make it slightly acidic, but not by that much in the grand scheme of things.
I know there are those that might automatically disagree with me... but so far I have had nothing but negative results from adding calmag. If you don't know that you need it, don't add it. Keep it simple. Get through the first grow and have some nice smokeable buds THAT YOU GREW YOURSELF, and move on from there. There is nothing quite like smoking buds you grew. Nothing.
Sorry I missed you again,
@Mike20132 ..........Thanks for the help..........believe me, I'm all about simplicity and lack of variables........that is what has driven my decisions thus far and I'm not gonna change, barring a major disaster!
It's an amazing path to go down, this thing of ours. Enjoy it as it goes.
Peace, friend.