So half way through this week this has happened an...

Nutrient burn from excess nutrient salts in your plants' substrate, usually from failing to water until run off each and every time. Easing up on the feeding will help prevent further burning, but what is showing up in the leaves now is what has occurred in the soil two weeks ago, so gentle/reduced feeding for the next half of the grow is best. Trying to solve the problem rapidly by flooding the substrate with heaps of water will not work, in fact it may make things even worse by dissolving even more locked up nutrient salts and releasing them. The problem has occurred gradually and so the solving of the problem is also a gradual process, which can't be forced. After looking at your diary, I would be halving the nutrient doses, but leave the "bud candy" at its current level. Your plants will be fine at this reduced amount of nutrients. Hope this helps, Organoman.