Yes, you have to get one of the ph test kits that has a higher range. Mine would be over 10 at times when I had problems with the plants.
That was years ago when I first started ponding. Lived in the desert and you couldn't have flowers, plants, gardens etc. as nothing would grow. So, I thought my answer was ponds but had just as many problems because the water was so bad. It was explained to me back then that the higher the ph, the less the plants are able to absorb any nutrients and they die.