Ok so I take it you are in veg state and using a flood drain system. if you are in veg I think your ppm is a bit high! I would bring down to 750-800 and see how they like it... I wouldn't get to high with your ppm till ya get the 12 hour light cycle.. Im using same nutes and have found that I have to use a lil less than what they suggest. different strains react differently though. as far as when you should flood, I use a drip system so I dont really know, but I watered 4 times a day for 30 min during veg