ph test

Hi all, just looking for some lived in recommendations for a good pH meter that I can use in a blackwater setup. API only goes to 6 which in a highly acidic environment isn't super helpful to a point. As I understand it, most typical pH meters aren't very accurate in water with zero gh, kh, or...

Hiya. I just checked my water pH in my planted tank with my ntlab testing kit and it came up as over 8. I double checked it with universal indicator paper which came up at pH7. I usually get a reading of about 7.8 and my water provider states 7.59. should I assume that both readings are wrong?