Was he not feeding them anything? They look positively starving - and starving most of all for some potassium (one of them REALLY shows that deficiency)... Some of them look better than others but they all look just plain hungry. I don't know what formulex is but I would probably add some H2O2 to the reservoir just to make sure there's nothing wrong with the roots...
Start feeding them a proper NPK nute and start a diary on them - keep us posted on how they're doing! I think you've got a good chance here!
Good luck ...