some more precautionary advise that may or may not apply. i tried doing my own ph cause i know someone that works in water and has expensive meters. so i took 1-1 soil / distilled water and coffee filtered it to try and get some somewhat clean water in a jar. then they told me 7.4. and my state university test told me 6.7 from the same dirt. i couldnt get anywhere trying to figure out why that might be. but that was different enough to matter.