1. Cut the silica. (I think you meant silica, not silicone) Too much will cause issues. Maybe give a small amount from here on out every other watering.
2. Stop watering to runoff. You are killing the soil by flushing all the microbes and stuff out in the runoff.
3. Stop worrying about pH because the soil auto adjusts it. Trying to change it will cause more issues.
I think the spots on the leaves are pH issues because you are trying to adjust it.
4. When you foliar spray, do it just before lights out to minimize the chance of light burns.
Read these and you will know how to water correctly and why.
Basic Watering
Discuss different watering methods for growing your own weed from seeds. Our community members give helpful tips on how pot size and material, as well as environmental factors affect growing cannabis.
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Watering SOIL
To know if you need to water your cannabis plant get yourself a soil meter. Poke or drill 4 holes in your pot 1/4 way up from the bottom spaced around the pot...
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