Autoflower issues - Week 2 flower

[LimaBravo]

Setup :
2x4 tent - 200w light - 3 gal pots w/ HappyFrog - Advanced Nutrients SensiGrow/SensiBloom

Seed- 420 fastbudz purple lemonade planted on 3/1

Hi all this is my 2nd grow, everything was going well with no issues up until 3 days ago after watering(plain) my plants I started to see the leaves go limp starting with the oldest growth and moving it’s way upwards. The leaves go limp then to a blotchy yellow rust then eventually die. Is there anyway to save this grow or is this it?

Thank you in advance

 

[Bill.de.Cat]

Since the nutrients that came in the HF would run out about 4/1, I hope you've used some of the AN nutes already. You haven't mentioned anything about the water your using.. IE.. source, pH level measurement ( of the plain water batch and after nutrient addition batch ). More info is actually needed to make a good diagnosis.
A better place for this might be in the Auto Infirmery where it'd get more veiws from people with a better knowledge base than I.

 

[LimaBravo]

Since the nutrients that came in the HF would run out about 4/1, I hope you've used some of the AN nutes already. You haven't mentioned anything about the water your using.. IE.. source, pH level measurement ( of the plain water batch and after nutrient addition batch ). More info is actually needed to make a good diagnosis.
A better place for this might be in the Auto Infirmery where it'd get more veiws from people with a better knowledge base than I.

Thanks for taking the time to respond, I fed them 1/4 strength then half, then full for the weeks in veg just before they started to flower. I’ll cross post over there I think I tried but my post count is too low.

I’m using RO water.
Plain PH - 8
Water w/ Nutrients - 6.5Ph
Run off after feeding - ~6
I’m using ph indicator drops. Maybe I need to invest in a pen.

 

[Bill.de.Cat]

A few possible issues there.
1. RO has nothing in it, no trace elements or minerals. You might be better served using a 50/50 mix of RO and tap or spring water to add a little bit back in. It's how I do mine and seems to work OK.
2. Nominal pH for soil ( HF ) I shoot for is usually 6 to 6.5 for any liquid. Best practice is measuring right before adding to plant ( plain or nute mix )
3. With soil, runoff measurement is not really needed, that's mostly for hydro types like CoCo from what I've read.
4. pH drops are fine, I started with them, and went back to using them after my expensive pH pen died.
With that additional information it appears you might be experiencing a bit of nutrient lockout. @Mañ'O'Green is our nutrient guru and he might look in since I tagged him and give a bit of sage wisdom or at least his nutrient chart that he has on speed dial.
Welcome to the site and ....feel free to ask questions, we try to help.

 

[Mañ'O'Green]

@LimaBravo Welcome to AFN .

Along with the PH being too high on the RO water when you measured it, It may actually be getting too low. RO water when exposed to air will acidify itself and can go as low as 5.4 or lower. You should aerate overnight then PH it. It really is a good idea to add back 50 PPM of Cal-mag to help stabilize it before you use it. Just mixing in some of your tap water can do the same thing.

You are way overfeeding your plant and it looks like the pots are sitting in the drain tray? This will cause the plant bottom roots to remain wet too long and anaerobic growth can cause root rot. Get an air gap under the pots. Get your nose close to the bottom of the pots and if it smells sour you need to get some Botinicare HydroGuard and use it ASAP. If it smells sweet and earthy you are in the clear on that but get that airgap.

Stop feeding those plants at least for 3 weeks just PHed water. They should recover.

 

[LimaBravo]

Sorry for the late response, a bit of an update on the plants things seem to have relaxed a bit but the damage was pretty severe on one. I’ve been leaving the water out overnight then adjusting a few hours before watering.

@Mañ'O'Green @Bill.de.Cat thanks for the tips, the know y’all gave me will definitely help on the next grow. Thanks guys

 

[Bill.de.Cat]

Sorry for the late response, a bit of an update on the plants things seem to have relaxed a bit but the damage was pretty severe on one. I’ve been leaving the water out overnight then adjusting a few hours before watering.

@Mañ'O'Green @Bill.de.Cat thanks for the tips, the know y’all gave me will definitely help on the next grow. Thanks guys

It's all a learning experience.