nutrient burn? again?

My clones had bad nutrient burn about a week after I got them. I flushed them with R/O water and only used plain water for four days. Then I gradually increased the nutrients to 200ppm, then 300ppm, until gradually I am now at 700ppm. I noticed today that the younger leaves are starting to yellow at the tips...again! I guess I have to flush it again with R/O water and then lower the nutes again? Should I just use pure water with no nutes for a week or two and see how it goes? THey don't really need nutes to grow anyway when they this small right? Someone help Please......

How often are you watering and feeding? I water around every 2-3 days and feed every sunday and havent experience and nute burn yet. I didnt start giving my babies nutes until they were in their 3 week and even then it was at a low dose. I was using MH maxiGro and I use maybe 1/4 of a tsp per gallon.

Wait a minute you only water every 2-3 days? Feed every Sunday? I guess I am "feeding" every time I water since the nutes are in the reservior below the tray the plants are in. The tray gets flooded and drained once a day for 15 minutes. I use a flood and drain hydro system. Am I over watering? Over feeding? Now I'm really confused.

My new plan is to use fresh water only for the next couple of days and then use a very small amount of nutes (200-300ppm) until they get a couple of inches bigger.

check tips if they are crispy its usally burn. If yellow but soft its nute defi. Thats just in my exp. Hydro is watered as much as needed or as much as u want. It depends on medium used. How big are clones and how well rooted

Yes the tips are crispy and yellow. A lot of the leaves on the plants that were initially burned from the first time have turned completely yellow, dried out, and fallen off. The clones are about 3 inches tall. I've had them for four weeks and they've grown maybe an inch. The plant that is doing the best has roots showing through the bottom of the rockwool cube. THe other ones you can't see any of the roots through the bottom.

i'm doing soil.....and thats the schedule i use for it....i'm not that sure about hydro...i would just use fresh water and use a really low dosage.

Dude I have bad burn right now too just flushed with 3× amount water to gallon ratio so with 9 gallons of water ..hope this works..

give them as little as you can without getting them pale.
Start at 300ppm and wait for them to get to a somewhat light green color, then raise your nutes.
Also check your pH.