When you tire of playing guessing games, perhaps if you were to fill-out the troubleshooting form we'll have this figured-out in no time. But this guessing game is costing you time and effort with little to no return.

The link is in my signature. Copy-n-paste the form here, and answer the questions as best you can.

Insufficient lighting and ph issues are a guess. Perhaps a good guess, but only in knowing the entire story, can we offer a valid solution.

Heck...could be something as simple as being drops of nutrients killing the leaf tissue. (can't let the nutrients splash or pool on the leaves, or dead spots will occur)

Miracle Grow instructions are for a two week period.