Please help! Wilting, yellowing, frustration!

I'm a first time grower, and I've been having some problems off and on with one of my plants. I'm growing OG with two 150w hps. Happy Frog soil, David's Grow - Grow/Base, Humboldt Honey every other feeding at half strength, 7 gallon pots. Also, just started using hygrozyme.

Basically the pictures show the problem. Tips of the leaves are yellowing and then curling up and dying. For a while I was having some problems with over feeding N, so I stopped the nutes and just fed clean water for a couple weeks, then started feeding again but only at quarter strength. Plant also is wilting quite a bit.

If anyone could PLEASE help me figure out what my problem is, I would greatly appreciate it.

If anyone could lend their expertise on this I'd greatly appreciate it!

You are probably still overnuting the shit out of it...

So...when you say 1/2 or 1/4 strength...what exactly is that based off? I mean yeah it says to do what a 4ml per liter or something? Thats all well and good, but if you are pouring 2-3 gallons of nutrients/water at a time...you are just adding more on top of what is already in the soil, but if you are only giving it a gallon of water in that 7 gallon pot, and your plants are large enough to sustain such water/nutrients it will be fine, but I have a feeling your plants are still a bit small compared to the pot size, so you've got excessive salts(nutrients) built up in your soil now. So you can either flush to correct it, or just go with straight water again...and probably straight water for a while...you may not even need to put a single drop of nutrients in the soil again at this point since your soil is chock full of it

Look over watered mate. Not sure about the leave tips could be nute burn or still n deficientcy

only real way to test if your soil has too much in it is to catch the runoff and test the EC of it...if you are running over 1200ppm then you've got plenty of nutrients in your soil that are not being absorbed yet...so give it time and let the root system do its thing...also don't overwater...only water when it needs to...if you close off the roots from oxygen that will in turn reduce their uptake of nutrients causing further lockout issues