Questions re: Flowering Phase - HYDRO

[Dannyboy58]

System info:

RDWC/bubbleponics with air pump, GH trio, calmag,koolbloom, hydroguard. ViparSpectra p2000 +

​​ two 100W LED grow bulbs during flower. 4inch exh, fan, one circulation fan in tent.

My Northern Lights are in flower. One plant is 19 days into flower buds are beginning to get thicker. Leaves look terrible. I know it's normal for leaves to start looking less than normal during flower but just wondering if this looks ok?

They're drinking about half gallon per day so I replace it once the level is down by 1 gallon and adjust to the pH back into range.

I've had a couple of big drops in pH in the last couple weeks but corrected them right away. I've also taken to checking at the same time everyday just to be consistent. The massive pH drop seems to be near the end of the week when it's almost time to change the res anyway but it's a concern...

Yesterday, Friday, the level was down half gallon from Thursday when I had added a gallon+, TDS was 470, 5.9pH. Today TDS 508, pH 4.3! Now I checked about an hour early today but WTF! So overnight they were thirstier than they were hungry for nutes but I don't think that's a trend. It's been more consistently a drop in pH and TDS or TDS has been fairly stable even as water lowers. I do compare my results to the feeding charts to determine if I need more or less nutes on the next water change.

Other related info, having a hard time keeping the RH down this week, staying in the 52-56 range for the most part. Was shooting for 45 during flower but as the other plants in the tent have grown the RH rises close to 60. Put a small dehumidifier in the tent yesterday to see if that helps.

SO 2 questions I guess to summarize...

1. What's up with the leaves? Related to the pH drops?
2. Anything I can do other than react to the pH drops?


EDIT:

When I looked under "Plant Problems" the brown spots lead me to believe it was calcium deficiency but I've been adding CalMag 1ml/gal of water. I use half the usual dose because my well water has a decent amount of calcium to begin with. It also says too much potassium can appear like a calcium deficiency. Maybe too much Kool Bloom and flora bloom combined?

 

[Dannyboy58]

By flush do you mean fill with pH adjusted and hydroguard water only for some period of time? Or just drain and refill with new nutrient water? That's what I did. I considered a flush with just water for a day but felt like it would be better for the buds if I went with the nutes and fresh water, since it was time anyway. I did go heavier on the cal/mag which has been a part of every fill and 2ml of hydroguard/gal. I scaled back the bloom supplements a bit as well due to concerns about potassium overload.

Thing is the 2 afghans in the same tub are perfectly green and thriving. They're a few weeks behind as they're just beginning to flower. Up to this point the afghans have been much quicker to respond to a nutrient imbalance but maybe it's related toor exacerbated by where the NLs are in the flower cycle right now.

i have multiple pH meters and keep them all calibrated. I'm pretty confident in them and even calibrate and retest if I get an unexpected reading like the 4.3 the other day.

 

[BU2B]

Dannyboy58 Q? Are your plants all in the same tub? I believe you said, 2 afghans in the same tub? When I first started growing Hydro indoors I learned pretty quickly that it's best to at least keep each plant in it's own tub or to limit each tub to the same strain for the reason(s) you've listed... Different strains often need slightly different and individualized care and nutrients.

 

[Dannyboy58]

BU2B yes 2 NLs and 2 Afghans share a 10 gal tote and roughly 5 gals of water. Won't be the case next grow.

 

[alltatup]

I agree that a flush is extremely important right now. I skimmed what has been written so far, so forgive me if I repeat. I would start with a 24 hour flush and then back down on the nutrients. Most of the time, when growers think it's deficiency, what's actually going on is NUTRIENT LOCKOUT, which makes everything look bad.

 

[Dannyboy58]

Thanks for the advice guys. I appreciate it. I was giving about half the mfg recommended dosage of the nutes based on other posts and advice but I added KoolBloom and increased the flora bloom when the NLs started to flower and may have been too heavy handed with it in my desire to fatten up my buds.

Here's something interesting though...When I changed the water the new fill was at 714 ppm, 6.4pH around 3PM Saturday. Sunday at 10PM when I checked solution was down 3/4 gal at 573ppm and 6.5. So if I believe the nutrient chart guidelines....lower water level, lower TDS/EC, and stable or rising pH is a good state. Plants are consuming water and nutes and not kicking out lots of acid, right?

I trimmed off a couple of the nastiest looking leaves because I couldn't look at them and they can't be beneficial to the plant at this point. A couple were kinda dry and crispy.

I have a feeling when I added the two 100w LED grow bulbs for the NLs they may have been too close and combined with the addition of the KoolBloom and maybe an imbalance like stated above it was kind of a perfect storm. The lights could explain why only the NLs were affected since the lights were pointed straight at them. The Afghans are considerably taller than the NLs, about 4 inches so the ViparSpectra light is further from them. That's why I felt I needed more light for them. I'll probably add another LED panel of some kind if I want to grow this many plants in the future. Next grow will only be 2 plants. I think I bit off a bit much for a newb.

I'm going to take both your advice, BU2B and alltatup , and flush for 24 hours with water treated with hydroguard and pH adjusted. Then I'll refill with a lighter nute solution.

BU2B yes that's the order in which I add the nutrients. Then I add Cal/Mag, Hydroguard and KoolBloom and THEN I adjust pH, pump the water to the res and check pH again, adjust if necessary. I check the solution every day and adjust pH as necessary topping off with hydroguard and pH adjusted water if it drops one gallon, then I recently read to drain and fill if you've replaced as much as the full volume before 1 week is out.

I realize now this is too much root mass and different requirements for one reservoir and I think that's a pretty big issue. Also believe it's just not enough solution for this many plants since 5 gals is about full capacity. Should be easier to manage next grow.

 

[RagWeedDWC]

By all means flush with RO water
Use Hydro religiously and I made the same mistake of pushing cool bloom, and my leave started looking exactly like yours.
How close are your light's? Old eyes but the leaves look a little curled.
If your able to have your water tested, I would so you can dial in your mag needs, or us R/O water.
ssss

 

[Dannyboy58]

Interesting to hear re: KoolBloom. Also not the first negative comment I've heard on it. I think i'll curtail the use of it for the rest of this grow...

The LED is about 22" above the NLs which puts it 18" above the Afghans, the minimum distance recommended by manufacturer. I also dialed it back to about 80% even though the guideline for flowering is 18-22" at 100%.

The 100w LED bulbs I added on the NLs were probably about 8" away at first. I moved them about 15" away last week.

I brew beer so my well water gets tested every year at Ward Labs. it seldom changes other than +/- .02 or so pH points.

 

[Dannyboy58]

OK, so I did a flush overnight and will drain and refill later this evening. I'm a bit "nute shy" now so the Kool Bloom will definitely NOT be used. I guess I'll go back to the safe and sure "half the suggested dosage" route on the GH trio with Hydro Guard.

How much CaliMagic? I think they recommend 2ml/gal and I've been doing 1 ml/gal.

 

[Dannyboy58]

I drained the flush and refilled with nutrient water, easy on the nutes, half the GH recommended amounts, maybe even a little less flora grow. I went with 1ml/gal of cal/mag which is what the label calls for.

Tuesday night after fil - 5.25 gals, 615ppm, low micro and grow, half Rec bloom, c1 ml/gal cal mag, hydro guard, 6.5pH added 5ml ph down. Ph 6.4

24 hour later, Wed 10Pm - 4.5 gals, 411ppm, 6.7 ph, Adj to 6.0.

So in 24 hours plants drank 3/4 gal, ate 200+ppm nutes and pH went up slightly. Good scenario right?!

I knew I'd need to add water today and the pH has been dropping drastically when the water level gets more than a gallon down so I checked just now.

Today, 1PM - 4 gals, 443ppm, 4.7pH !! Topped off with 1 gallon water with HydroGuard, 6.8pH, reservoir leveled off at 5.6. Will check pH again later this evening.

Why the massive pH drop every time I get one gallon low? Maybe because of crowded roots in the tank? I know I'm suppose to check about the same time every day but that's a huge drop and doesn't seem like it would recover almost a full point of pH a few hours later in the day...

Damaged NL plant looks Ok, no further spotting or brown leaf tips but of course the damaged ones haven't recovered either.

Afghans still look super healthy and the second NL looks ok too.

 

[Dannyboy58]

Do you think the drastic drops in pH I'm seeing just a few days after refill are due to the crowding in the tub? I start with 5 gals in the tub and they seem fine as long as it stays above 4 gals but as soon as it drops below there the pH level drops below 5 and yesterday as low as 4.0! Maybe it would be better if I put a deeper tub under them for now? It's not like I can take any of them out of the tub now that their roots are so big. I suppose I could change out the water every few days too but that would be a PITA.