plant problem please help

ok i think its a Potassium deficiency. the tips of my leaves have curling down and i see a few small yellow spots. i had just topped off my tank when i seen the problem so do i need to do any thing esle or will the water and nutes i just add help that? Or should i add baking soda to fix the problem

i would say you are correct.

check this out though Cannabis Nutrient and Deficiency Table

so i should just leave it alone or add bakeing soda

baking soda is sodium bicarbonate. that has no potassium in it. i would say first check your pH. if your pH is off, then flush the plants thrououghly. maybe even switch pots(if they are early in growth.) if they have a good pH, then get an npk fertilizer that is high in K. If you dont have any of this and the condition worsens considerably b4 u can get some, u can sprinkle a small amount of wood ash (from fireplace) on the soil and then water.