Tap water is the first no-no of hydro that I noticed that could be causing your problems.... And I say this from experience.... When I first went hydro I used tap as well.... They grew, what I thought at the time, fine.... Until late veg/early flower is where I started noticing negative changes in the plants.... Posted questions on here, I was told to switch to RO and haven't looked back since....

Check the ppm's of just the tap water before adding nutes and then ask yourself, WTF is in those ???ppm's....

I'm almost 100% positive that if you stop using tap and start giving them RO + nutes & micro nutes, they will recover quickly....

Oh and if you decide to get your RO from a vending machine type of water dispenser, make sure the ppm level is less than 25.... Sometimes those machines are just pouring out straight tap water and people are none the wiser.... That's why I love my ppm meter....:jointsmile:

CGI::::::