Please help me try and save these plants

[Vb2flat2surf]

I've posted before how I suck from weeks 1 through 4. I mess everything up as I'm a noobie and still learning alot. After week 5 I've done well these last 2 grows. HOWEVER, I'm on day 74 since seed, my plants were looking AWESOME until a few days ago. One of my Bruce Banner Autos sugar leaves all started turning brown. It hasn't got worse by any means which I guess is good, but just last week they were so pretty and frosty. I figure they will dry up and be cut anyways at trimming time. Or am I wrong? Is my plant looking that bad (the picture of just a bud) that it's gonna be garbage weed? Then my other plants were looking perfect and green and healthy and now the leaves are all turning brown.
The only thing I know I did wrong was I accidently double fed my plants by making my mix way to strong by accident. A day after realizing what I did, I did a flush with 6.5ph and 30 percent runoff but nothing is getting better. (My runoff reading was 6.6ph)
I was really stoked about these plants and want to know what to do. I love smoking Bruce banner and am looking forward to harvesting my own. Any help would be appreciated.
GROWING IN: FoxFarm Soil
NUTRIENTS: "Grow Big" and "Buds and Blooms", Humboldt plant Enzymes (no longer applying), CalMag (haven't used in 2 weeks)
LIGHTS: Mars Hydro TSL2000 AT 20" ABOVE CANOPY
3 GALLON MESH POTS
WATERING EVERY 3 DAYS

 

[mysticepipedon]

Looks like light burn. Any nutrient issues are a moot point now.

Just slug it out until the end. You'll have some decent, smokable buds, they're just not going to be pretty their last week or two.

BTW, don't water by the clock or calendar, water when the soil is mostly dry.