I'm 2-3 weeks into flower and just tested my water. Ph7.5-8. I believe I have nutrient lock out. So I have been giving them the bad ph this whole time. Also I believe the growth is slow fast. What should I do. This is my first grow. Orange sherbet autoflower.

Using a few drops of pH down in your water isn't going to eradicate your microbe population. So don't be shy to lower the pH; the plant will produce much better when the medium is in the proper pH range.