Can water PH be adjusted by sunlight exposure?

I have been testing my soil with a soil testing kit i bought for $15 at the local hardware store. I tested my soil PH of a plant i was having problems with and it was 7.5 so i adjusted the water with some lemon juice and then tested the water with the soil testing kit and my water was reading off the charts for highly alkaline even after i adjusted with a little lemon juice. I was wondering if the water itself is alkaline. I use a large swimming pool to treat my water for iron and other heavy metals so my first thought was possibly sun exposure? I also wonder if it matters that i am using a soil testing kit and not a water testing kit.

Can anyone help?

i tryed using a soil test kit on my water aswell and the same thing happend, i went down and bought a fish tank test kit and it said the water was 6.4 and the soil meter read about 7.8

sweet that makes me feel better. I hope it is reading my soil correct!

they have a soil tester at lowes that is kinda like the fish tank one it seems to work good, you use these little pills and water runoff from the dirt it was like $7 out in the greenhouse area