I was GOING to say you were spot on, but taking a look at your diary, although you're hitting them a little heavy with the Acti Vera and the Bio Heaven, neither of these has any NPK in them so it's got to be that your soil is just a little too hot for them. I would do as you plan - just plain water, probably for a week, and see how they do. The only other cause of that would be overwatering - the state of being CONSTANTLY wet - but I think you'd see more drooping than clawing... In any event, make sure you let the soil dry out thoroughly before giving them anything more and do this every time you water/feed.
Good luck - and Merry Christmas (if you celebrate that particular holiday!)