I personally have grown in ffof for 5 years now...water for first 3 weeks and then start the foxfarm trio nutrients...never had a problem ..If i were too guess i would say they are about to get nute lock out from to much potassium if your using flower and bloom nutes because they are loaded with...
Man.... me personally would try and save it..scrape off the nutes and repot w perlite sphagnum moss or coco...seedlings feed themselves for at least 2 weeks
I legit got my 24x24x55 mars hydro tent and ts600 mars hydro light, carbon filter,intake fan, exhaust fan, ducting ,tent humidifier, and oscillating fan,for 350-400 on amazon but all that is cheaper now but I agree "LIGHTS" are most important as I've learned ...if you got to the mars hydro...
Yeah... starting to get the hang of it...just dropped my (gelonade,bubble runtz,tropicana poison) photo girls.. cant wait to see the Tropicana poison produce red flowers