leaves yellowing in vedge

They need more food. There are signs of deficiencies in all three macronutrients. In order of severity, P,K,N. Don't flush because it will make deficiencies worse. Give them a very strong dose of fertilizer that is high in Phosphorus. Personally, I'd use a tea made from a mixture of high-P Guano and either Maxicrop or Kelp Meal. The damaged leaves won't heal but once the problem is fixed, it won't spread to other leaves. Keep in mind that pot plants can handle stronger concentrations than are listed in almost any fertilizer's instructions.

 

Phos def. give it some bone meal in a tea for faster action.

 

Well it would depend on what's in the bloom feed. Here's a pic of Potassium deficiency. Note the similarity to the upper fan leaf in your second pic. It's a little small. I need to get a new K-def example pic. The more I look at the pics, the more I'm thinking that the K-def is actually worse than the P-def. Phosphorus deficiency causes the damage toward the leaf tips that in more severe cases curls upward or in a corkscrew pattern, patches of necrosis in seemingly random spots and deformed new leaves. Potassium deficiency causes the damage along the edges of the blades and downward curling.

 

Here's a pic of how K-def can present when combined with some P-def.

 

Nitrogen is the most common nutrient in potting soil. Almost all degrading plant matter releases Nitrogen and so any good, soft soil has some. The plants that were flowered and given flowering nutrients likely recovered because what the plants are lacking are Phosphorus and Potassium; the flowering nutrients.

The little ones in the new pics look pretty good. They need more Phosphorus. Phosphorus is the nutrient pot plants need the most of in their lives. During veg, use almost as much P as N; about 80% as much. Plants like yours that are already showing deficiency damage can temporarily get even stronger doses of it. The best sources of P include Bone Meal and high-P Guanos. These should be either mixed into the soil for slow release or made into teas for manual fertilizations. Bone Meal is best made as a hot tea because it doesn't mix very well in cold water. You'll also want to use at least half as much Potassium as Phosphorus. You might want to make this half as much K as N for awhile, since you've been having K-def problems. This makes the vegging ratio come to a nice 10-8-4 to 10-8-5. With the proportions right, all that's left is to find what concentration your plants can handle.

With the exception of seedlings and rooting or just-rooted clones, always use the full fertilizer concentrations suggested by the manufacturer, if not more. Pot plants can handle alot of food and nutrient deficiency is a much more common problem than nutrient burn. Just make sure to alternate feedings with plain waterings. Among other benefits, this gives the plants time to display any signs of burn before the next feeding. You can find the ideal fertilizer levels by increasing the concentrations suggested by the manufacturer by about 20% at a time. Watch the lowest and oldest leaves. Nutrient burn will start at their tips. Once you see some burn, pull back to the previously used concentration. A little burn on the lowest leaves is a very minor issue. I always try to get some slight burn on the lowest little leaves during flowering so I know the plants were fed as well as possible and yield as much as possible.

As always, regularly check the soil pH until you know your whole feeding regimen keeps it in the correct range. The soil pH is a separate test from the pH of liquid you use. You can test soil pH with a liquid pH tester by getting pure water and verifying its pH. Water thoroughly and allow the plants to sit at least a couple hours so that the water has time to take on the pH of the soil. Squeeze some water from the soil, often by pressing on the surface and collecting the runoff, and test it.