nute burn

ok 2 of my plants were over nuted for about a week. i changed water with lower ppms and am seeing the top leaves curl downward, now was i supposed to have gave the plants no nutrients for any amount of time to flush the plant or was i alright with just switching out the nutrient solution?i am using 7 mil per gallon of pure blend pro 7 mil pg of hygrozyme 10 mil per gallon liquid karma. ill post some pics when the light comes on all answers are appreciated thanks

heres some pics

You probably should have flushed until you saw signs of deficiency. Where is the nute burn? Also, I would only use liquid karma during flowering.

lt liquid karma huh? ill have to check it out. yeah, i would have used plain phed water.