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woodsmaneh

woodsmaneh

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I was talking about DO (desolve oxygen), when saying it is hard to put to much oxygen in the water without very expensave equipment. University Of Gulph in Ontarion Canada has a study on it.

As far as air causing to much presipatation of the elements that's possible.

Just wanted to clear that up.



Higher dissolved oxygen great for productivity, health and vigor
Research > Learn About Research > News > Higher dissolved oxygen great for productivity, health and vigor
________________________________________
By Robert Fieldhouse
(Guelph, October 13, 2005)
Dissolving more oxygen into hydroponic solutions could boost greenhouse productivity and provide a whole host of other benefits too, say University of Guelph researchers.
Prof. Mike Dixon and Dr. Youbin Zheng, Department of Environmental Biology, are investigating the positive aspects of using an oxygen diffuser to increase oxygen levels in greenhouse hydroponic solutions used to grow roses, tomatoes, cucumbers and peppers.

Dr. Youbin Zheng, Department of Environmental Biology, is studying if oxygen levels can be boosted in hydroponic solutions to help growers ward off harmful microbes and boost productivity.

Photo credit: Olivia Brown
Preliminary results suggest a higher dissolved oxygen level increase productivity, health and root vigor in greenhouse plants, and helps keep harmful microbes in check.
“These findings are really beneficial to the industry,” says Zheng. “If we can use oxygen to boost plant health, making them stronger and more resistant to disease, we've discovered a very helpful tool.”
Oxygen isn't as prevalent in warm water as in cool water, so oxygen levels tend to be low -- about two to four parts per million (ppm) -- at high greenhouse temperatures, compared to eight to nine ppm in cool water. Under hot weather in the greenhouse, the root zone is especially short on oxygen, says Zheng, because root respiration depletes oxygen in hydroponic solutions. Excessive watering can further depress oxygen levels because it makes growth media, such as rockwool or coconut fibre, less porous, blocking air. These factors all weaken plant disease defense systems, making them more susceptible to disease-causing microbes such as Fusarium and Pythium which cause root decay.
To prevent this problem, greenhouse growers typically bubble air into hydroponic solutions to bring oxygen levels up to about nine ppm. But sometimes this still isn't enough.
Two years ago, the BC Greenhouse Growers' Association asked Dixon to investigate using even higher oxygen levels in hydroponic solutions. His literature review revealed that very little work had been done in this area suggesting the problem was largely ignored – until now.
Dixon and Zheng are using an oxygen diffuser recently developed and manufactured by Seair Diffusion Systems Inc., an Edmonton-based company with an interest in the greenhouse sector. The diffuser concentrates atmospheric oxygen, and dissolves it into hydroponic solutions. With this technology, oxygen levels can reach as high as 60 ppm in hydroponic solutions.
The research team is currently studying the effects of different oxygen levels, ranging from about nine ppm to 40 ppm.
So far, preliminary results are promising. But creating optimal supersaturated oxygen solutions requires extreme precision. Oxygen can be damaging at very high levels, says Dixon , so it's important to establish application methods for using this technology for different crops.
But if the methods can be worked out, Dixon says the oxygen diffusers are inexpensive and stand to emerge as an economical, environmentally friendly solution for growers looking to enhance their crops.
“Greenhouse growers are voracious technical consumers – they'll try anything,” says Dixon . “But by the same token, they're also very shrewd business people, and they won't waste money unnecessarily.”
Dixon and Zheng will continue their research and will further investigate oxygen's effect on plant growth, physiology and disease. For example, they will inoculate greenhouse plants with specific microbes to see how the plants cope with this challenge under different oxygen levels.

Other researchers involved in this project include technician Linping Wang, graduate student Johanna Valentine and undergraduate student Mark Mallany, Department of Environmental Biology.

This research is being conducted at greenhouses in Guelph and Leamington , Ontario . It is sponsored by Seair Diffusion Systems Inc., Flowers Canada Ontario and the Fred Miller Rose Research Fund.
 
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phup

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Thanks for the info on DO saturation systems.

And no, I do not use ozone in the room.

Quick question Woodsmaneh: How high above the canopy do you keep your lights in early veg? At 50%, 75% or 100% intensity?
 
woodsmaneh

woodsmaneh

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I use the back of my hand method, hold my hand, palm side down just touching the top of the plant. If I feel any heat I move the lite till I don't feel any heat and that's where it goes. I do that with everything T5's (not much heat) 400w, 600w and 1000w. I start my clones under a 400w and 600w and my seeds go right beside them.

Ozone kills the smell but too much will damage plants kind of like yours, so was just checking.
 
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ant87stang

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hey whats up guys, currently running 2nd run of uc. strain jack herra. i am using cal mag in system and are still getting cal mag looking def. i was told to use at 3 ml a gal, but read above to only use at 1ml / gallon. any ideas? plants are in 4th week vegg, look great other than that, and have great roots and are eating nutes like champions!
 
UCHQ

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What symptoms are the plants expressing that make you feel they are CM def? Pics would help.
 
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ant87stang

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the normal rust spots and lighter green in middle of leaves. i will get some pics
 
P

phup

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Update: Plants look significantly happier with RH at 55%. I have reduced aeration by 50% and raised lights to 5' above plants. Still not sure about the aeration hypothesis as I have plants in an aeroflow in the same room that are exhibiting the same signs.

Sys 2 had ph rise from 5.8-6.0 with Ppm remaining steady at 360
Sys 3 had ph rise from 5.8-5.9 with ppm remaining steady at 260
Aeroflo had ph rise from 5.6-6.0 with ppm dropping from 500 to 490 (0.7 conv)

What's with the ppm's not decreasing? That has been the case for 3 days now even though plants look perky.

Check out the pics to see the progression of these deficiencies. I cannot decide if I am overfeeding, underfeeding or if the plants are locking out. New growth, however, looks pretty good.

My hypothesis is that I am not swinging my ph low enough (having trouble staying below 5.8) and am getting micro nute deficiencies as a result.
 
Jan 27 AF
Jan 27 sys 2
Jan 27 Sys 3
UCHQ

UCHQ

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Plants look dehydrated which is a good indication you've got osmotic disruption, likely due to the excess of some mineral in solution.

Micros are plentifully available at pH's ranging from 5.5 - 7..especially for plants that size that necessitate little more than water to grow.

A) Reduce your CM dosage to balance your mineral ratios.

B) Avoid frequent adjustments of pH, as plants will tend to exhibit issues similar to what you are seeing when nutes are tied up as a result of the adjustment.

Plants have grown very well for years and years well before the advent of CalMag. When plant growth rates accelerate and the plants begin to demand more calcium to develop new growth tips and bud production...then it may necessitate the addition of CM.

Bring down your total ppm by simply dropping CM....Cal., Mag, Iron are all accounted for in the nutrient solutions ur using. Trust the nutrient formulators know what they're doing when they blend these nutes.
 
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hollywood7

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Dose it matter were you place the airstone in the module ie side middle i was thinking of putting on the side this time last time it made a hollow area in the middle!of the root mass any thoughts?
 
Maitreyah

Maitreyah

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Plants look dehydrated which is a good indication you've got osmotic disruption, likely due to the excess of some mineral in solution.

Micros are plentifully available at pH's ranging from 5.5 - 7..especially for plants that size that necessitate little more than water to grow.

A) Reduce your CM dosage to balance your mineral ratios.

B) Avoid frequent adjustments of pH, as plants will tend to exhibit issues similar to what you are seeing when nutes are tied up as a result of the adjustment.

Plants have grown very well for years and years well before the advent of CalMag. When plant growth rates accelerate and the plants begin to demand more calcium to develop new growth tips and bud production...then it may necessitate the addition of CM.

Bring down your total ppm by simply dropping CM....Cal., Mag, Iron are all accounted for in the nutrient solutions ur using. Trust the nutrient formulators know what they're doing when they blend these nutes.

Hey UCHQ,
I've got a thread in the infirmary
My question to you is:
If my ppm is dropping is there a chance that I'm still overfeeding? My ph is rising and my ppm is dropping and I'm getting what looks like the claw. Also, some of my leaves mid plant look like they may have a cal mag deficiency
thanks
 
johnnyrex

johnnyrex

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Hello UCHQ thanks for the advice about the white slim on my roots they have been washed with tepid water like you said ppm drop to 200ppm it's been 2 weeks since that and growth started to take off. I was starting to wonder why it's taking so so so long for the plants to start growing. One of the 4 basket started to poke 2 roots out, I was wondering I have a bootle of H&G root exc..

When can I add this product cause I what to see so root explosion and if so what what rate can I apply this thanks once again for all the info.
 
UCHQ

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Dose it matter were you place the airstone in the module ie side middle i was thinking of putting on the side this time last time it made a hollow area in the middle!of the root mass any thoughts?

Middle is typically best...or on the inlet side of the module.
 
UCHQ

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Hey UCHQ,
I've got a thread in the infirmary
My question to you is:
If my ppm is dropping is there a chance that I'm still overfeeding? My ph is rising and my ppm is dropping and I'm getting what looks like the claw. Also, some of my leaves mid plant look like they may have a cal mag deficiency
thanks

The claw is more likely N excess...I'll check your thread.
 
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Hello UCHQ thanks for the advice about the white slim on my roots they have been washed with tepid water like you said ppm drop to 200ppm it's been 2 weeks since that and growth started to take off. I was starting to wonder why it's taking so so so long for the plants to start growing. One of the 4 basket started to poke 2 roots out, I was wondering I have a bootle of H&G root exc..

When can I add this product cause I what to see so root explosion and if so what what rate can I apply this thanks once again for all the info.

Consider preparing a 5 gal bucket with RE solution and performing a root dunk of each net pot them returning them to the system. Then add a 1/4 strength dilution on RE into the system and monitor.
 
johnnyrex

johnnyrex

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Consider preparing a 5 gal bucket with RE solution and performing a root dunk of each net pot them returning them to the system. Then add a 1/4 strength dilution on RE into the system and monitor.

UCHQ first thanks for the advise 1/4 strength of the recommended dose of the bottle?
And what strength do you recommend for the 5 gal bucket or also 1/4 strength of the recommended label dose? Thanks again for taking the time to answer all of us
 
johnnyrex

johnnyrex

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hello UCHQ another question it was taking a while for these clones to recover from the white slim they had on their roots, but about 3 days ago my R/H was a little low at about 40-45% and i saw your chart and it states that you would like R/H to be around 70% in this stage so i brought in a wet towel and that did the trick R/H id now at 70-75% not higher. After i did that the plants started to grow everyday like crazy i dont know if its coincidence or what.

Now i have notice that the leaves have wrinkles on them as you can see by the fotos dont know what can it be PPMs 250 water temp 63-64 ph swings from 5.3 to 6.2 than i bring it back down again. Day tems 75-77F night temp 73-75F, Day and night R/H stay the same 70-75% can it be that i have 4 fans 1 on each corner could it be the wind i have each fan on the lowest setting, the only light that's on is the vertical one in the middle which as of right now is at 500watt I havent turn on the 2 horizontal light as i want the plants to grow roots out the bottom before i put all 3 light at 1000w so please help with this issue thanks
 
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UCHQ

UCHQ

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hello UCHQ another question it was taking a while for these clones to recover from the white slim they had on their roots, but about 3 days ago my R/H was a little low at about 40-45% and i saw your chart and it states that you would like R/H to be around 70% in this stage so i brought in a wet towel and that did the trick R/H id now at 70-75% not higher. After i did that the plants started to grow everyday like crazy i dont know if its coincidence or what.

Now i have notice that the leaves have wrinkles on them as you can see by the fotos dont know what can it be PPMs 250 water temp 63-64 ph swings from 5.3 to 6.2 than i bring it back down again. Day tems 75-77F night temp 73-75F, Day and night R/H stay the same 70-75% can it be that i have 4 fans 1 on each corner could it be the wind i have each fan on the lowest setting, the only light that's on is the vertical one in the middle which as of right now is at 500watt I havent turn on the 2 horizontal light as i want the plants to grow roots out the bottom before i put all 3 light at 1000w so please help with this issue thanks

Plants look good..sounds like your on the right track.

1/2 strength on the RE root drench.

The humidity may have likely helped the plants fully hydrate after their issues with the slime hampered their H2O/Mineral uptake.
 
johnnyrex

johnnyrex

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Plants look good..sounds like your on the right track.

1/2 strength on the RE root drench.

The humidity may have likely helped the plants fully hydrate after their issues with the slime hampered their H2O/Mineral uptake.

Ok that great but I then guess that you saw that the pics of the plants look great what about the wrinkles on the leaves do I have to worry about it or it's nothing thanks
 
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