Leaf discoloration

Hello,
This is my first grow and i am having some issues and i can't figure out what it is. Some of the leaves are a bit yellow in tint and some are looking beautiful.
Can experienced growers like yourselves help me?

Thanks in advance

Overfeeding. Flush with fresh pH'd water, let dry, repeat. Back off on the nutes 1/4 to 1/2 and keep track of your pH.

You've probably got a Ph a problem, there could be some overwatering, and the brown tips of those leaf spikes on the new growth looks like Potassium and/or Calcium deficiency. Overfertilization would start with burning the very tips of the bottom leaves.

I believe it's exhibiting signs of potassium and magnesium deficiency due to pH lockout - from overfeeding, didn't mean to imply they are over fertilized. High soil salinity/pH locking K and binding Mg is common when full strength nutes are fed every water cycle (assumed, first grow). Even well draining soils can accumulate salts/residues and should be flushed with just pH'd water on an alternate schedule. Sorry for the brief answer previously, was in a hurry.

So let me get this straight. I should flush with pH'd water and reduce the strength of the nutes and only use it every other cycle?

Well that's my opinion anyway, I usually use a schedule of feed:water:water:feed:etc. and I let mine dry completely between watering (well not now, doing a hydro scrog now but in past grows). It's also important to check your pH, what you put in but also what drains out, I suspect you'll see a big jump the first few times but it should level off. I'm a big fan of H2O2 as well and add it every time I water (1 cap full/gallon). As far as nutes go, I always start with way less than recommended then slowly increase until you see the tiniest signs of stress/burn then back off a little bit.

ScrogThis,
I'm a noob and i've been overwhelmed with all of the nutes out there, what is your recommendation? Also, what type of pH meter should i get. I've seen a couple that you just stick into the ground and it gives you a reading for about 10 dollars at Lowes.

Thanks for all the help

Get a soil Ph tester. Ask the store clerk what their better and worse models are. Even if you can only afford the cheapest one (10$ Lowes model), it should tell you the correct soil Ph but it may not last very long. There are little plastic ones where you just mix a little soil with water and some powder. These are usually the cheapest way to go. They aren't as accurate as a mechanical or digital soil reader but it's reading doesn't become less accurate over time like the others do. We use these to compare readings with our soil meters every once in awhile, seeing if they're still working correctly.

GH makes good nutes so does Technaflora, Humboldt, Fox Farms, etc. Most any name brand is okay, read the internet reviews for any tips like "mix 1/2 strength" and such. I personally use Technaflora as they seem very consistent batch to batch and I have yet to burn my plants with them. I tend to shy away from "fads" like Gravity and those types of things, if the feedback is 50/50 or less just leave it alone. Any pH meter is ok to start, even a cheap pool test kit is ok to keep you in the proper range. A decent quality starter meter is something like the Hanna pH meter, ~$30 online (the little red/black one), they hold up fairly well and tend to stay adjusted, the probes are replaceable as well. If you get a meter pick up a small bottle of pH reference solution (usually 7.0) to keep your meter calibrated once/week. Usually organic nutes don't have as many issues w/ pH fluctuation and lockout due to the processes that break down the organics into a usable form, Mother's Finest can probably expound on that. The most important thing is to know your plants, look at them carefully everyday and you'll see immediately when they are unhappy, get a feel for what they want and you'll be fine.