please help leaves dont look normal

hi ,
i have 2 (mobydick) in hydro wilma 4 pot
clay pebbles
800w hps
temps 28 deg celc light on
20 deg light off
humid average 40-50
currently 5 weeks in veg ,,, they have been main lined to have 16 tops
all was fine until transplanting into wilma pots . transplanted 1 week ago
had wilting due to underfeeding , then over feeding...
sort of fixed ,,, how often should i water in clay pebbles ?
ec of 1.6 ph 6.0
new tops looked deformed like twisted and slightly burnt
any help please ?

Plants aren't getting enough O2. Check your rez temps, warmer water won't hold O2 like colder water. Also check for root rot or plugged bubblers.

I've never liked those Wilma pots; they're a magnet for fungus gnats, and like you point out; bitches for root rot.
I put extra air stones in, and liquid oxygen...
(Only used with clay pebbles though, I think it would work easier in soil)

From what i can see you have a problem with overwatering, stop watering them so often! Second problem i can spot is that the root's do not have enough O2, they can't breathe (that is a problem that comes with clay pots). They can't breath because you water them too much! Let them be dry for a day or two before you water them.

Try soil next time