Please help identify persistent deficiency late flower

So I've been dealing with a deficiency in my current culture rdwc clone system.

Everything is identical down to their lids with the exception of the air pump I use. I'm using the ecoplus commercial air 1 rated for 38 lpm (I think their system ships with a 28 or 32 lpm pump)

I've had this deficiency with different nutrients (cultured solutions and canna)

I'm using a chiller water temp 65-67 (just installed these recently, but deficiency just started again) currently canna aqua flores (which I'm finding the ph to be way less stable than the current culture nutrients (cultured solutions)

Keep the ppm 750 and under on the 500 scale. Currently I'm at like 450/500 on these girls and they didn't eat much (1 week to go today) so I'm going to lower the ppm to 350 or under tomorrow.

Current culture recommends low ppm and if I go over 800 they stop eating or much slower anyways.

Anyways plants look perfect till about week 5/6 then they get a deficiency that progresses until harvest actually leading burn on the buds themselves causing a trimming nightmare because then I'm digging into the buds cutting out weight...

This time it seems to have come on a bit later... I just switched to magical (techniflora) a few weeks ago to see if that would help... I'm using 4 ml per gallon gallons (160 ppm on 500 scale)

The systems tops off on a float with uv filtered ro water at 0ppm direct from the ro filter (not sitting in res)

So yeah, perfect looking plants, week 5/6 through harvest I see some leaf deficiency, quickly spreads to buds, progresses through harvest. Some strains seem to be effected worse than others.

Could it be I need even more calmag in the mix (current culture recommends 1ml per gallon for their nutrients, every other company I talk to says that's not enough with 0ppm water) and I'm currently using 4ml per gallon

Please help this has been going on for a while....

So close to switching back to dirt but I get good yields, ease of use and I have a ton invested into all these systems.

Thanks!

what kind of lights are you using and how do you cool them?
how far are the lights from the canopy?
what is the ambient room temp? what is the temp at the canopy?
im leaning towards heat and/or light stress. your calmag dose should be ok. i use 4-5ml/gal with r/o water with no issues. it does look like you could ease up on the nutes a little though, those leaf tips look a little rough.

I didnt read anything about your pH levels. Where are currently at?


Figuring out nutrient issues is a guessing game. Lets start at the pH and work from there.

Yeah I hear ya, ph levels almost always between 5.5-6.5. I try to let it ride if ibn those ranges. However canna aqua Seems to be much less ph stable (canna actually recommended I use the canna subatra since it isn't 'ph corrected' and supposed to be more stable in these systems...)

The cultured solutions was extremely ph stable ( very slow drift up add they ate) but still had the issues then too.

Also seems the last couple weeks ph wants to go down at am increased speed, ppm also continues to go down too

Right now I think the ph on that system is 5.6

5.6 should be just fine.

Buffering capacities (pH stability) are important when formulating nutrients. We went through a lot of R&D to get it just right.

What conversion rate are you using when you're stating your PPM levels?

Also room temps 75, rh around 40-50, 1000w single ended 1000's air chilled. Lights are a bit too close but no other options with my setup... Thinking it's not the lights because this will sometimes happen on plants side branches farther away from the lights...

500 conversion. What nutrients do you sell perfect grower?

We sell the Perfect Grower line

RH is better at 70% in veg and 55-60% in flower. Humidity is your friend. Just make sure you have good air movement and it doesnt get above 65%.


Too low and your plants won't grow as fast.

I was also thinking maybe there is some bad bacteria in the rubber return line from before I had a chiller... I'll change those as a percussion

It's always a good idea to rinse your equipment and lines with a light bleach solution, especially if you've had unwanted microbial growth in the past.

I always sterilize with bleach every grow for 24 hours... Just a thought...

Be careful, bleach also oxidizes. Dont want to damage pumps or expensive water chillers. It doesn't take very long for bleach to kill things

Any other input as to what might be going in here? Plants look great till late flower like I said, anyone???

I wish I could help on the nutrient situation. I don't know techniflora's formulation. It's a guessing game for anyone.

What are your roots looking like?

Have you looked for bugs? The way the leaves are tacoing looks like broad mites or a heat/humidity problem

Roots look good, thick and healthy... Water cooled at 65*

Rh is 40-48

I know shoe people like rh higher but that shouldn't be it...

I'm trying the super low ppm on plants coming up (maxing out around 350-400ppm on 500 scale)

Using current cultures supercharged feed chart recommendations on ppm.

..What do you guys think? I've heard people never really getting higher than 300 ppm on these systems doing well...

For a system like yours, in flower, we recommend an EC of around 1.4 (PPM 700 on a .50 conversion).

That's what I've been using up to this point... So frustrating

Looks like over feeding to me.