you have calcium deficiency

and you have magnesium deficiency

add 1 tsp of epsom salt per gallon of water you use

also add 1 tsp of hydrated lime per gallon of water you use

make sure u use distilled water

and make sure the shit is disolved, hydrated lime is hard to find order it from somwhere

both of these problems slow down the growth of the buds, and make the leaves turn brown on the ends and curl up slowly