The black knobbly thing is the pot itself - airpots or rocketpots over here in Aus. They wrap around the medium and are held together by a rod. They allow for air pruned roots which branch out, rather than having them coil up inside the pot. Big roots = big fruits!
@Teetee have you calibrated your ph pen recently mate? Maybe the start of ph lockout? I think N def usually starts low and works its way upHope you get them sorted out soon man, their real beauties
I'm a soil and sun type of guy, so I could be way off....please take what I say with a grain of salt as I don't even have a ph meter
I think you've hit the nail on the head Bro.... my pen was a little off, but the issue I have is an acidic medium as you will see later in the post.....
cheers for the input mate, yeah, it's pH issues.
Hey Tee sorry to see you've hit a few issues with a couple of your ladies.. hope you get them sorted M8
I'm onto a plan mate, lets hope it works out.
They need N for sure Iree, but they can't take it up cos the pH is so acidic in the medium.
Yeah, I remember that.... I'm tempted to flip, but being greedy and having gone this far, I wanna see if the sick ones can recover a bit before I go 12/12.
I always seem to have one plant per grow that does this at about week 5 ish, be they Autos, or (now) Fems.... I'm thinking this is a pH Coco issue?
Funnily enough, I remember always getting a bit lazy with the feeds at around this time and instead of daily waterings, I end up feeding every 3 days for a bit, then panic when it all kicks off.
They've been drinking and leaving an over-concentrated medium.
Having said that, although the coco looks dry, it is moist under the surface..... only PAK2 has felt a bit light after 3 days.... and she's the healthy one obviously cos she's drinking while the others aren't (as much).
I always use the same brand Nutes and Coco.... House and Garden. I looked at their website, and noticed they heavily wash out the coco.
I think this has reduced the so called buffering capacity of the coco, so on Wednesday I decided to do some tests.
First, I did a flush with EC 0.8 feed. I made some up 2 days before as a 'holding feed' until I worked out what to do.
I've always been reluctant to do a plain water flush because I worry that the Trichoderma and pH buffering capacity of the Coco will be washed out too...... they say you should NEVER water coco with anything less than EC 0.6 because of that. BUT, now I do plan to give a plain water flush based on the findings below......
SO... after giving an EC 0.8 flush to the big 3 at around 11am Wednesday, it was pH 5.8, and 26°C going in.
The room temp is managed by AC and stays at 26°C
Inside the tent, I get a max of 31°C and a min of 26°C, lights on 18 hrs, and dark between 12 noon and 6pm. RH is between 69% and 77%
First 250ml run off details as follows.... but I get about a litre of run off in total after giving 6-7L to them and they are in 25L airpots.
- Des Frans EC 1.9 pH 5.4 29°C
- Gorilla EC 2.0 pH 5.3 30°C
- PAK2 EC1.8 pH 5.5 29°C
Pretty obvious to see the Coco is too acidic and the Girls have locked out.
Now the next problem..... my equipment.
I have a Bluelab Guardian, a Bluelab EC Truncheon and also their pH pen....all about 6 years old, except the pH pen which is 3 yrs old.
As I said in post 1 of this thread, the Guardian's pH pen is out of action.... I haven't pulled my finger out and sent the whole unit back to Bluelab in NZ.
The reason why.... I still use the EC bit. My Truncheon gives a lower reading, so I only use that for mixing.... an expensive mixing rod!
The pH pen, well I had to calibrate it on Wednesday... it wasn't far off, so I think the pH's are reliable.
Then I remembered, I have some Bluelab 2.77EC conductivity solution..... yep the Guardian is spot on and the Truncheon is EC 2.3. As far as I'm aware, it's uncalibrateable.
Back to the tests...
Later on Wednesday, at 7.00pm I did a plain water flush... it was pH 5.9 straight out of the bucket, so I didn't bother fiddling around with pH down to get it to pH 5.8.
Water temp 27°C Tent temp 29°C RH 74%
I gave them 5 Litres each, standing by with the big 50ml syringe to catch the first 250ml and an aquavac for the rest of the run off.
Here's the run off details..... not good......
- Des Frans pH 4.8, EC 1.5, 27°C
- Gorilla pH 4.4, EC 1.5, 28°C
- PAK2 pH 4.6, EC 1.8, 27°C
- PAK1 pH 4.5, EC 2.2, 28°C
As you can see, at my current pH nothing is being absorbed.
I decided to fix this by re-alkanising the medium.... it has to be a gradual process without stressing the plants out. The idea is to increase the pH of my feed by 0.5 every day until the run off becomes pH 6.3.
So on Thursday, I made up a strong Sodium Bicarbonate solution. I got a litre of my usual EC 0 base rainwater, heated it up and dissolved as much Sodium Bicarbonate (Baking soda) as possible to make a supersaturated 'Molar' Bicarb solution.
I managed to get the pH of the Molar solution up to pH 7.9. I asked the eminent Scientists at Google, and they reckon the pH of a freshly mixed Molar Bicarb solution should be around pH 8.3, so I wouldn't be able to get it much higher than that.
I also made up 40L of an EC 0.8 pH 5.8 feed, got it to pH 6.3 (using the Molar solution as a pH up).
I gave them 6 Litres each, and here's the run off details...
- Des Fran pH 5.0 , EC 1.2, 29°C
- Gorilla pH 4.9, EC 1.2, 29°C.
- PAK2 pH 5.1, EC 1.7, 30°C
- PAK1 pH 4.7, EC 1.9, 30°C
Visually, there was no change, obviously. This was the first pH adjustment, so there's a long way to go yet, but at least they are heading in the right direction!
Last night I gave them the same EC 0.8 feed as the night before, with a bit more of the Bicarb solution to make it pH 6.8.
Here's the run off data....
- Des Frans pH 5.6, EC 1.2 32°C
- Gorilla pH 4.9, EC 1.2, 32°C
- PAK2 pH 5.1, EC 1.2, 32°C
- PAK1 pH 5.3, EC 1.5, 32°C
Still, the data for the DF looks the most promising, the pH is rising the quickest, and the EC's are dropping for all of them.
Day 43 update.
Let's start with the group shot.....
They are all growing, despite the pH issues, but some better than others.
PAK1 is toddling along, gaining millimeters each week in height. She is 20cm tall now, having grown 5cm in the last 6 days.
She's looking pretty healthy....
PAK2 is also looking reasonably healthy, but beginning to show signs of trouble lower down....
Her stems are nice and thick, and she stands at 58cm. She was 45cm last week, so she seems fairly happy.
Des Frans is also growing at a terrific rate. She is the tallest at 60cm, but her stems are thinner, and of course there's all those pale and yellowing leaves.....
I'm waiting to see if those leaves go green again after all this horsing around with the pH.
FInally Gorilla. She's 42cm which is just 2cm growth in the last 6 days.... not a happy bunny at all.....
She looks like she's begging for some Nitrogen, so I'm planning on making a different feed for her and the Des Frans that will have less base nute, and more N, keeping the EC at 0.8. Then all the usual pH balancing with the Bicarb.
I'm thinking about what to do when they recover... I'm hoping within the next week....
One idea is to put a net over at about 40cm, then supercrop the taller stems of the PAK2 and Des Frans, open up the canopy, lift the PAK1 to the same height, give them another week to veg then flip 'em.
Another thought is to put some stakes in and tie down those bigger stems....
What do YOU think???
So that's it for now, I'll continue posting the pH figures each day. Thanks for popping in!
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