I don't know how much light you are under, but 1200 (as people have stated) is very high for plants that size. I would be about half that right now. Peak at 1200, if even that high. I would want the plants to be about twice the size you have before flipping. Keep tying them down, spacing them and filling the scrog.
Your nutes are .5 scale, so 1.4 ec = 700 ppm. 800 ppm would be 1.6 ec etc. The two most common scales are .5 and .7.
1 ec on the .5 scale is 500 ppm. 1 ec on the .7 is 700 ppm.
I think we already had this conversation, but a top feed that really soaks everything every 4 hours will trump the feed system you are using. Your solution is not only too hot, but your plants aren't eating well. See
@EventHorizan 's pics...that's what yours should look like.
I measured my buckets and the water level is 7" below the top of the buckets.
I think I gave you my recipe in another thread. This is a RDWC scrog with that recipe. Remember I use c02, so my mix is much hotter than you can run. But a rough idea is if you are 600 watts, 600 ppm.
Do you see how your plants are much more sparse looking? Something is off. I think it's the heat of the feed and not having roots. In 10 days or so once roots fill in, they should take off.
Imo you should try a top feed system. Something that turns the solution over every 4 hours. It will cut your veg time down significantly.
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