First timer with sick plant

[billspreston]

Greetings folks, first time grower here running into my first sick plant. I have 4 different strains growing right now and only 1 of the plants is showing symptoms. The sick plant is pretty healthy overall but the larger, older fan leaves are starting to look pretty gnarly (crappy photos attached). They develop these dark brown spots and then start to dry up and turn yellow starting from the tips moving inwards. I've been trying to figure out what the issue is by reading guides and such, but many of the deficiencies look similar to me so I'm hoping you guys can help get me on the right path here. Sorry for the crappy photos, you're help is much appreciated!

Strain of Mj?
X18 Pakistani

Hydroponic or soil?
Soil (FFOF)

From seed or clone?
Seed

What stage (Veg/Flower; how many days into)?
8 Days into Flower

Container/Pot size?
3 Gallon Air Pots

Water runoff Ph?
?Unknown

Nutrients added?
BioBizz Bio Grow, BioBizz Bio Bloom

Feeding schedule?
2ml Grow, 2ml Bloom, 1L of water every other day

When were they last fed/watered?
2 days ago

How are you determining when to feed/water (weight, wilting, etc.)?
Weight

Tap/RO/Distilled water?
Tap Water, left sit out for at least 24 hours

Ph before and after adding nutrients?
?Unknown

Is your Ph equipment properly calibrated?
?Unknown. Not with the program in the Ph department. Figured I would be safe using organic soil, but maybe that was a poor assumption.

Light intensity/Age of bulb/Wattage?
400w HPS, new bulb

Distance to the canopy?
8-10 inches

Temps at canopy?
73-80 Degrees

Day/Night temps (Min.-Max.)?
65-73 Night, 73-80 Day

Current air flow (CFM)?
6" Can Fan

Is there air blowing directly onto plant?
2 6" clip fans blowing from underneath canopy

Using CO2?
No

Relative humidity?
30-50%

Growing technique (Scrog, Sog, Supercropping etc.)?
Scrog

Has plant recently been pruned, clones taken, fimmed or pinched?
Plant was accidently topped while training 14 days ago

Pests?
Not that I'm aware of.

 

[Snype]

Sorry to say this but you have to get your self a pH tester and get your pH down to 6.6 - 6.7. pH is very important.

 

[Snype]

You're also feeding nutes way to often for soil. You need to nute every 7-10 days and in between just add water pH'd to 6.6 - 6.7. Follow these steps and you're on your way!

 

[billspreston]

You're also feeding nutes way to often for soil. You need to nute every 7-10 days and in between just add water pH'd to 6.6 - 6.7. Follow these steps and you're on your way!

Thanks for the encouragement Snype. Not sure why I've been so stubborn about testing Ph. I recall seeing the price of the Hanna meters when I first got started and suppose I just ended up putting it off. Can I just use the plain old paper testing strips as a reliable testing method for my water? I'm thinking that would probably work fine for me. I'll cut back on the nute frequency and use more regular H20. Should I worry about flushing the soil of excess nutes or just let things run their course? Does 2ml of each Grow & Bloom every 7 days sound reasonable to you moving forward? Your guidance is much appreciated.

 

[Snype]

Flush them out by putting twice the amount of water of the size of the container and make sure it's pH'd. pH all your nutes and everything at the end. Yeah you can use the pH strips.

 

[Snype]

I've used a lot of product but not the Bio Buzz. Start off by using half the recommended dose for flowering but don't use any nutes in VEG because you have FFOF. As you get closer to finishing start cutting out the Nitrogen

 

[billspreston]

Hey Snype, I'm 8 days into flower now and I did not feed any nutes for the first 30 days of Veg per suggestions with using FFOF.

I went and got some Ph strips today and to no surprise my water Ph was very high at 7.8. I'm kicking myself because its probably been like this the whole time and it was something that was so easy to correct. I lowered the Ph down with vinegar and watered all the girls. I'm going to hold off on flushing for now because none of the plants seem to be too bad. The reason for holding off on the flush is because I'm doing a Scrog and it would be tough to pull off. I will figure it out if I need to go that far, but I'm hoping by correcting my Ph things will get better over the next few weeks. Thanks brother!

 

[billspreston]

My plants seem to be recovering and they are looking great! New growth seems quicker and darker than ever before I picked up a Hanna pH meter and some Phosphoric Acid to use for pH Down instead of using vinegar so I think I'm the right track now.

 

[reckon]

Thanks for the encouragement Snype. Not sure why I've been so stubborn about testing Ph. I recall seeing the price of the Hanna meters when I first got started and suppose I just ended up putting it off. Can I just use the plain old paper testing strips as a reliable testing method for my water? I'm thinking that would probably work fine for me. I'll cut back on the nute frequency and use more regular H20. Should I worry about flushing the soil of excess nutes or just let things run their course? Does 2ml of each Grow & Bloom every 7 days sound reasonable to you moving forward? Your guidance is much appreciated.

test strips are actually MORE accurate than most meters costing less than $150, (unless you calibrate the thing before EVERY USE) are very inexpensive, and falling off a sofa is harder to do.

just get some strips, or the liquid/vial/color chart PH test kits available at any hardware/nursery type store, so you KNOW, and don't have to guess

you can always get the meter later, but for now just get the PH checked and corrected before things get worse as everyone has already suggested.

 

[compost]

I am a hard luck case with over fertilization in soil myself(never a problem with hydro).
Its easy to keep adding the ferts when the plants are growing and look good. I myself got one of the kits from lowes that not only has the PH tester but also testers for NPK. I used it to make myself realize I was giving them way to much nutes. Sometimes seeing the test results will hit home better then what peeps are saying.