Lemon Jeffery first grow (black thumb)

This week I experienced my first unhappy plants! There was some brown tipped leaves (probably nitrogen burn from the coffee grinds. I guess that wasn't the best idea. Also have some likely light burn on the two left plants, Georgina and Jewel. I raised the lights on that side to about 15" above canopy. On 3/29, I flushed the plants with tap water until water ran out of the plants. Then I flushed each plant with 2 gallons of ph adjusted and filtered water. Hopefully that will fix it!