Dying plants, please help

Your Equipment:
.1) Type and wattage of lights. 4 Bay 24â?� T5 from SunSystems
.2) Distance from tops? 3 inches
.3) Reflector type? Included in T5 array
.4) Is there a consistent fresh air supply? yes
.5) Do you have an exhaust fan and a circulation fan? Yes
.6) What are the bulb wattages, kelvin ratings, and schedule? Two bloom spectrum, two veg spectrum, 20/4

Your medium:
.7) Specific brand and type of soil, (fertilized soil) and anything you've added to it. (vermiculite, perlite, worm castings) FoxFarm soil-less mixture, supplemented with worm castings
.8) Size of container. ~8 gallons [Earth Box growing unit]
.9) Did you use peat pucks (or similar) to root clones or germinate seedlings? No; germinated in final medium

Your nutrients and water:
10) Source of water? (tap, bottled or filtered) What's it's ph before adjusting? Tap, 6.8
11) Method of checking water ph. (ph pen, test strips, aquarium test kit...) test strips
12) Method of adjusting water ph. (phosphoric acid, white vinegar, hydrated lime, PH Up...) Have yet to use
13) Specific brand and N-P-K ratio for each bottle. List dosages (quantity per gallon) and current feeding schedule. General Organics BioThrive [4-3-3] and BioRoot [1-1-1], every 3-4 days
14) How often are you watering between feedings, and how much per watering? Feed via reservoir in EarthBox
15) Any additives or tea's? (Superthrive, CalMag, molasses, Mother's Earth...) Yes; Molasses, Peruvian sea bird guano, Mexican bat guano, earthworm castings.
16) Are your ph levels stable, or do they fluctuate? Stable
17) What is your ingoing water's ph? ...your runoff ph? 6.8 â?? No runoff, contained system
18) Do you foliar feed? If so, with what, how often, and at what time do you spray? nope

Your growroom:
19) Indoors or outdoors? indoors
20) What size of closet, room or hut? self made hut, area= 6 feet wide, 3 feet deep, 10-11 feet high, closet
21) What are the temps and humidity levels while lights are on? ...With lights off? lights on: 72* controlled environment, 60-70% humidity
22) Have you seen signs of insects in the growroom? None

Your strain:
23) What strain are you growing? (Indica dominate or Sativa dom?) Afghan Kush Ryder, C. Indica, 22%
24) From seeds or clones? Seeds
25) Is this an autoflower strain? Yes

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Attachment 278030

Appears to be signs of over fertilization.... Ever fill that earthbox res with just plain water??? How do you measure nutrient strength???

CGI::::::

Yes. I put nutes in maybe.... once every two weeks? I'm trying to run on the same fertilizer pattern as I did on my last grow [which had pretty nice results].

Should I sledgehammer it and remove the salts and start over? I mean... literally, 2-3 weeks from right now, it's going to be done. Am I totally effed for having an end result to enjoy?

I don't think you're totally effed but they are a bit stressed and will most likely be delayed if you can resolve the issue....

You say that you only nute every two weeks??? Water every 3-4days??? Maybe your probs are due to deficiencies....and I bring this up because you are using a soil less mix.... Think about using a medium that has soil in it for your next go, like FF Ocean Forest or FF Happy Frog....something that cannot be used as a hydroponic medium....

What is your soil pH??? I don't recommend using tap water but that is just me....could also be part of the prob....

No runoff??? So does the excess water sit at the bottom until the plants drink up the moisture??? Not understanding this portion of your setup.... Is it a recirculating water system??? You doing hydro or soil???

Also, if you think there is a build up of salts, you can always flush the medium/roots....

CGI::::::

An earthbox is a self contained unit. EarthBox has all the information.

The water sits in the bottom of a reservoir and there are two bricks of mix in the back that wick water up in to the soil. I top feed with the nutrients, and then fill the reservoir with water. I'm going to do a R/O water flush here in the next minute or two, no nutrients at all, just R/O water. I'll report on the progress over the next day or two.

Found out my caretaker has been doing an organic feeding schedule, and we think there may, in fact, be too much guano/castings in our mix for the plant. We're going to flush some of it out and hope for the best without having to recondition the soil with so little time left. We're scheduled to cut by September 8th. I just.... god I hope this works. It'd be such a tragedy to lose her at this point.

Yeah....hope it works out for you too!!! Chances are, if you have only been giving nutes through topfeed, salts have been building so flushing with RO will help....flush twice....

CGI::::::

Your caregiver has made a mistake.
BioThrive and BioRoot are amendments, not necessarily fertilizers. Somebody isn't paying attention to the bottle's contents. What you need to do is give an NPK ratio and you can do this with BioGrow if you want. I usually recommend Dynagro fert, however, as it has most of the micronutes plants need. There's nothing wrong with what has been given, but a shot of nitrogen will cause those plants to green up. What that happens, consider growing them for a longer period, to recover and produce more. I'd get the Dynagro because your plant is showing yellowing at the top, which means you're missing a particular micronute. Dynagro fert will supply this. Read the back and you'll see that for a soil grow, you use 1/4 to 1/2 teaspoon per gallon of water. You can continue using R/O if you want, but in my opinion it is better to go to the store and get bottles of distilled water as R/O has some salt to it. Only water when the top inch of soil goes dry.
Dyna-Gro You shouldn't need anything else.