Why Are They Turning Yellow/burning?

[Peff]

Rh of 20% is low, but certainly not too low to grow a successful crop. I'm often skeptical of relying on hydro shops for fixing problems, as they have a direct financial interest in treating any problems you do, or don't, have. I'm not saying that your shop is crooked, I am just saying that they sometimes sell you stuff that you might not really need. Sometimes.
I think that people tend to overthink and overworry about their plants, panicing every time they see a spot or curled leaf tip. I have used the same semi-minimalist recipe for 30+ years and have never had a problem other than one of my creation. As long as the plant has enough nutrition, root space, enough light and water...you will be good. Plants don't really need much nutrition for the most part. A bag of good potting soil will grow a decent plant even if you don't pour potions and enhancements into the soil. Larger containers allow a few pluses...more room for roots, more soil to hold nutrients and water, and it acts as a buffer, preventing wild Ph and nutrient swings that are hard on plants. It helps to keep the Ph in the sweet spot, which is probably the most important issue since everything goes to hell when the Ph is wrong. Nutrient lockout and related overfeeding, ie chasing your Ph tail, is only one problem.
Sorry for the Sunday morning rant I have a buddy that is constantly adding stuff that the local hydro shop recommends, despite having a lot more problems, like you are seeing, he keeps buying and adding stuff that has caused him problems. Any changes in his crop is mostly psychological, IMHO, as he is always having problems that aren't really problems. I use an analogy with cars. 95% or more of cars on the road today run fine on the available gas. Unless you are a professional or very serious racer, regular or premium gas will suffice. Putting racing gas into your car doesn't make it go faster until your car has the modifications that require the high quality racing fuel. Remember, you are talking about your everyday car, not a specialized dragster that needs to get every bit of energy out of the gas. Plants are the same way...give them food, light, water, and a growing medium, and they will grow well. Can you get more out of them by using the special soils, fertilizers, and every other item known to man? Sure...but only to a degree. You might get another 10 or 15%, but you are typically seeing the increase due to the extra care you give them, such as daily pruning and other small things that add up over time.
I would transplant them into bigger buckets/bags with decent grow mix and see what happens. Once they get some room and better soil they will probably take off.

First off all thanks a lot for the help

Its funny you say that because I go to two different hydro shop, and there was this old man ( another customer ) that I saw at both placesWe got into a little conversation, and he told me the exact same thing: "Hydro shops are looking to sell you stuff more so than anything else " lol, but he did recommend himself that I try peroxide + water on the leaves for the first night, and then Water + growth plus ( called " Ben Johnson"? Its algae ) + the Bug B Gone.

I'll add another picture, seems pretty obvious to me that I have insects in my other tent ( leaves have holes and they kind of eaten ) so I figured why not use it in the other while im at it?

They were in 5.5 inches pots and the pictures I first posted were when I had just repotted them in an 8inches pot. They were due when I repotted them as the roots were definitly visible in those small holes in the pots. That should help too right? The RH was raised from 20 to 40-50% since then ( goes up to 50-60 during the night ) and I feel like they've gained back some green.
When I repotted them, I gave them water until there was a 20%~~ runoff at the bottom ( so not too big but not small drips of water either ) and they're still not dry enough ( imo, cant lift them easily with one arm and using the finger in the soil trick ). Am I overwatering? Is that " fine"?


As for my nutrients, I go feed-feed-water, using
Week1: A+B Growth 9mL/L
Calmag 1mL/L
BioWorm 6mL/L
Gruv 1mL/L

Wk2: AB Growth 11.5mL/L
Magnesium nitrate 2,5g/L
Rhizotonic 4mL/L
CalMag 1mL/L
BioWorm 8mL/L
Gruv 1mL/L

Wk 3-until flowering: A+B Growth 14mL/10L ( 1.4/L ) , magnesium sulfate at 1g/3L
Rhizotonic 4mL/L
CalMag 1mL/L

 

[Jimster]

I'm a promix user and I don't think it's possible to overwater anything in it as it doesn't hold water too much as long as you have 4 or more drain holes(1/2 inch is fine) on the bottom sides and bottom itself. It seems to hold just the right amount of water but can dry out quickly when the plants get big. I just use a general 20-20-20 fertilizer, some wood ashes for calcium, trace minerals and elements, and maybe some Epsom salts. The Epsom salts are for the magnesium, but mag isn't needed in great quantities and usually isn't needed if you use any type of actual soil since it is usually already present. I mix composted manure to the promix for the remaining micro and macro nutrients and that's it. I feed them about every 10 days with generic ferts, although I step up the P and K a little during flowering. I give between 1 and 1.5 gallons of water/day/plant and usually put a small tray to collect runoff and make it available to the plant to keep from drying out too much between waterings. I usually water until it comes out the bottom, although some strains need different amounts of water compared to others.
There are a TON of little things that you will learn to do over time...it's experience and there really isn't any other way to do it besides getting your hands dirty. You are doing a good job but don't overthink it. Like I said earlier, with the basics met, you can get up to 95% of the plant's potential. All of the extra stuff makes a difference, but only after you learn the basics and get that experience under your belt. Remenber...you can always add fertilizer...once you add too much, your plants will suffer greatly before they can be remedied...IF they can be fixed. Keep up the good work!!

 

[Ina]

Thanks, its pretty dry where I am though so I dont think thats really an issue as its now 40% RH with 3 humidifier ( goes between 40-50% )

They were due to be transplanted as the roots were visible in the pot's little hole at the bottom.

Are those spider eggs? Or the white thing thats in Promix? The guy at the hydro shop told me to watch for those

These are spider bites,the mark they leave when they eat.Check the downside of those leaves for small moving dots.You should take off the leaves that are infected(as much as possible without killing the plant)and than spray,clean,spray,clean ….:)You are already late but still you have to check,convince and hurry up.You have to wash everything.Getting humidity up is also good idea(they like dryness and dust) but you have to clean them all,clean the pots and everything that goes into the grow space,also the growspace itself.If you succeed to clean them(it is not easy)than you can transplant and it will probably resolve your other issues(wet the new soil a little before use,it makes it easier to water),once the infestation is stopped.