ph question?

I got my Sentinel E&G system all set up and ready to go! I'm waiting on my mother plant to clone from. I've got a ppm ph meter, and my ppm is 26 and my ph is 9.01. Even though I don't have anything to grow now I still wanted to watch my new system run, so I let run for the day and I checked my ppm and ph after running for 24 hours. My ppm is 218 and my ph is 5.4. I'm using hydroton as my grow media. My question is when I finally get to put my clones in the buckets should I wait 24 hours before I start trying to adjust ph? Is it normal for waters ph to change in a 24 hour peroid with no nutes added? I'm assuming that my ppm changed because of dust or something on the hydroton even though I tried to wash them good. Is my assumption correct? Thanks very much for all of your knowledge.

Can i see a pictures of your set-up?

PH can fluctuate really fast in water with no solutions to stabilize it, my guess would be the hydroton is what also caused your PH to drop. Especially if you just rinsed them in some lower ph water.

It was just a bad reading, it happens.. Measure twice fuck up less. Really that could not of happend... Measure your tap water.. PH/PPM/./ write it down... you rez water should be the same. ( if tap water with nothing added)...