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How important is negative pressure?

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#11 madgoose

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Posted 13 October 2020 - 06:40 AM

 

Morning mate, thank you for your input and for suggesting a chat with "forest". It is always a good idea to have a good chair to go with the literature, sometimes I just sit on a chair and look at my garden, the plants can tell you so much about what is going on if you know what you are looking at. The Jorge Cervantes book that I mentioned tells you the affect that nutrient deficiencies and heat or humidity issues will have on the leaves of the plants. If you can learn how to "read" your plants then you will learn what adjustments and changes you should be making now to see results for your actions in a weeks time.

 

What does the "build quality" of the Lumatek feel like, is it rigid or does it feel flexible? And is it a metal framework or some sort of plastic/nylon? Do you know the weightof the unit (don't worry if you don't it should be easy to find)?

I like the 1000w ballast I have of theirs it feels solid, sturdy and well constructed with good quality components it does not feel like the output selection dial will pull or snap off.

 

So, I have just been outside to take a quick look at things whilst waiting for the kettle to boil. After the error yesterday evening I ran both the intake and extraction fans throughout the light and had a temperature of 35C this morning. I have given them a "half feed" with a diluted nutrient solution and will continue to do this twice every 24 hours whilst I combat the heat and humidity issue instead of one large feed in the late afternoon as I had been. 35C does not concern me to much because I have grown and harvested during summer months with that temperature but I would like to get it down and have more control over the temperature. If push comes to shove and I feel that the higher temperature is a concern and is detrimental to the end result I can always turn off one of the lights and reposition the other two so that they can properly cover the area.
 


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#12 symbol 22

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Posted 13 October 2020 - 06:51 AM

Everything you saying about reading the plant is bang on ... I'm going to order that book you mentions with regards to deficiencies!!.. Best way to describe the lumatek is .. If you have ever ownd a lumatek ballast before.. And that quality, superior feel!! Well the panels feel the same ... Exactly the same! Strong solid and very nice to look at ... Mate they look the absolute mutts nuts!!

Or you could introduce an aircon unit that's what I would / and have done in the past... There absolute pennies and work fantastic ...
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#13 madgoose

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Posted 13 October 2020 - 11:05 AM

 I'm going to order that book you mentions with regards to deficiencies!!..

 

 

Marijuana Horticulture: The Indoor/outdoor Medical Grower's Bible by Jorge Cervantes

https://www.amazon.c...s/dp/187882323X

 

I still like to hold a book a turn pages but I have had a search and managed to find you a PDF copy that you can download for free, when you click on the download select the PDF version...

 

https://www.pdfdrive...e199814728.html

 

UPDATE:

 

This morning I have unplugged the intake fan and the temperature rose from 35.5C to 37.5C so i plugged the intake fan back in. I then disconnected the ducting from the carbon filter and the temperature remained the same at 35.5C, this tells me that the carbon filter is working OK because I thought that after being stored and not used for about 6 years maybe the carbon had settled and compacted itself, this does not seem to be the case. Later today I will swap the 150mmL1 RVK with the 200mm RVK SileoE2 with 200mm - 150mm reducers before and after it. In the mean time I have switched off the middle light off just to see what kind of temperature is produced. If it lowers the temperature to the high 20Cs then I will reposition the 2 lights after testing the 200mm RVK should that not manage to lower the temperature. After testing the situation with the 200mm RVK I will probably leave that set up and if it cannot reduce the temperature to high 20s to low 30s or at least low 30s with 3 lights running then I will set the third light to come on for just 9 hours in the middle of the 18 hour pattern. This I feel will emulate a warm morning, a hot midday and then a cooler evening. Maybe I can benefit more by trying this method as it would create a more natural feel to the plants rather than just a scorching hot day for the whole period. Who knows? Give it a go and see what happens. They definitely do not like the low humidity because the leaves are starting to curl under which means that they are trying to reduce the amount of moisture they are losing through transpiring. I was planning on starting a foliar feeding regime when I reduce the hours to 18 hours of light come Friday. Because I like to foliar feed either just when the lights have turned off or about an hour before they come on I will postpone that until then.


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#14 Anonymiss

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Posted 13 October 2020 - 11:24 AM


Knowledge, reading is the key.

 


I still like to hold a book a turn pages but I have had a search and managed to find you a PDF copy that you can download for free

 

Yep, can't beat an actual book-in-hand, but have you discovered The Book Library?

 

That'll keep you busy! ;)

 

 

eta: There are also torrents for those who prefer that sort of thing or who want the whole collection in one go.


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#15 symbol 22

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Posted 13 October 2020 - 11:25 AM

Hey thanks for that !!! Just DL it now ....I tend to foliar feed right up until I get signs of flower I use a mix of superthrive and the a-and-b feeds.. That's all I ever tend to use throughout my cycle!

Thanks again
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#16 madgoose

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Posted 13 October 2020 - 12:02 PM

Yep, can't beat an actual book-in-hand, but have you discovered The Book Library?

 

That'll keep you busy! ;)

 

 

eta: There are also torrents for those who prefer that sort of thing or who want the whole collection in one go.

 

No, I had no idea it even existed thanks for showing me, what a treasure trove. When I get some space on my hard drive I WILL be downloading those gems! I can see a few titles that I actually have the physical books, but that one called "Compost Everything" might have to come home with me tonight, I was just talking to my Mum about her using a composter. Thank you again Anonymiss,
 


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#17 madgoose

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Posted 13 October 2020 - 12:22 PM

Hey thanks for that !!! Just DL it now ....I tend to foliar feed right up until I get signs of flower I use a mix of superthrive and the a-and-b feeds.. That's all I ever tend to use throughout my cycle!

Thanks again

 

Cool.

 

That is what I do to, up until bud formation and stop, I don't want to risk making it to hospitable for mildew of fungi. My foliage regime consists of wetting agent (I was told by a reputable source but I have not tried it that it can be substituted for washing up liquid and you only need a couple of drops per liter,) I then use a couple of products which I believe are no longer manufactured. VHO (Very High Output) which was made by Advanced Nutrients and designed to produce new shoots on mother plants. I bought a liter of it back in late 2009 and still have half of it left, you only need a few drops at a time.Directions read: Foliar only! Mix VHO to 300 ppm above the waters normal ppm for the first 4 days and with 4 day intervals increase the by 300 ppm until you hit a max of 1200ppm above the waters ppm. I then use another product by Dutch Masters called Liquid light which again has been discontinued, when I realised it was getting hard to find I found an outlet doing it on special because it was a slow mover for them and I bought 10 liters of it. You are supposed to use it with another product of theirs call Penetrator but I can no longer find it for love nor money. I believe it is an Amino Acid based product, I will have to get the bottle out and read the back, when I do I will take a picture so you can see what it contains. Basically if you had both of their products you would add 60ml of each to your final spray solution.

 

Always wondered but I have never found anything/anyone to answer my question. Should foliar feed be PH corrected and if so to what? I always use it as is because i don't know differently.


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#18 madgoose

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Posted 13 October 2020 - 05:13 PM

Subscription for a digital copy of "Garden Culture Magazine" its a good read covering methods and products, once you receive your first copy email then and ask if they can send you some back issues, most grow shops should have hard copies which are free

 

https://gardencultur...#subscribe-form

 

UPDATE:

 

I have not had much time today to do any refitting in the garage but i have made some adjustments and monitored the results and I think I have made some headway. I have had to bring my tomato, pepper, chili plants indoors so that the fruit on them which is well developed does not rot and also my baby avocado trees that I started from seed back in April because of the rain and cold weather we are experiencing. I have had to clear a space in the kitchen and put up some shelves, then I fitted my maxibright T5 4 tube light over them on a timer to subsidise the quality of natural light and the amount of hours of light that they are receiving and more importantly so that they are warmer at night, this will ensure that they ripen.

 

Throughout the day I have made some small adjustments to the grow room. This morning I unplugged the intake fan which increased the temperature to 37.5C so I plugged it back in and it came down to 35.5C. I then disconnected the CF to make sure that it was not clogged, which it is not so I reconnected it. I then turned off the middle light and unplugged the intake fan for an hour which reduced the temperature to 33.8C and the humidity was 25%. I then plugged the intake fan back in which reduced negative pressure but also after an hour the temperature had come down to 31C and the humidity had risen to 31%, after another hour the temperature had come down again to 29.5C and the humidity has risen 33%. I let another hour pass and checked again and the readings were steady at 29.5C and 33% humidity. In another hour i will go back out there and check that the calibrations are accurate and take the readings again. Whilst I am out there i will top up the humidifier and give the plants a half feed of a diluted nutrient solution.

 

Tomorrow I have to buy some soil and compost to mix with the manure that I got from the farm at the top of the road some months back and then re-pot the 2 plants i am going to flower in some 78 liter planters that I have, I also have to pot up some seedlings that I have out there. Whilst I have everything out of the grow room I will drill some holes in the ceiling and fit some hooks to reposition the 2 lights for better coverage and to hang my box fans, i will also take some photos for you so you can have a visual of what i have been trying to explain. I took some a couple of nights back but they were over 8mb.


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#19 madgoose

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Posted 13 October 2020 - 06:30 PM

Can you not go back to your previous post and edit them? For example to add photos now that i have worked out it is quite simple.

Marijuana horticulture

Intake & oscillating fans, small oil radiator & humidifier

Extraction set up

Grow Room external

external grow room shot

Suspended box fans
Chilling in the kitchen
Tomatos & basil plants
78 liter planter
Outdoor raised veg bed

 

 


Edited by madgoose, 13 October 2020 - 06:48 PM.

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#20 Anonymiss

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Posted 13 October 2020 - 08:37 PM

 

Can you not go back to your previous post and edit them?

 

Yes, but only for 60 minutes (I think).


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