stalebiscuit
Well-Known Member
didnt see the date to be fair. but it being a forum an all other people can read it and chime in. ya know, rolling conversation and what not
DWC res too cold???
- Thread starter resinraider
- Start date
rkymtnman
Well-Known Member
i realize that, just letting you know not to expect a reply. that is all.
Keesje
Well-Known Member
There are more ways, and perhaps using an airstone is not the best way.
stalebiscuit
Well-Known Member
im all ears for new methods lol. i was wondering if he knew something i didnt
Fonzyyy21
Well-Known Member
Yesss sir there's science behind it, water holds the most dissolved oxygen at 64-68°F best for your plants!!!
Honestly though as long as you don't go past 72° you should be good! Nasty stuff start growing then!
I run around 70-71 at the hottest part of the day (in the tent) and I don't seem to be having any issues!
Honestly though as long as you don't go past 72° you should be good! Nasty stuff start growing then!
I run around 70-71 at the hottest part of the day (in the tent) and I don't seem to be having any issues!
Keesje
Well-Known Member
You are not right (which is something else then wrong)
But there have been numerous science based posts about this, that I will not answer it.
The word 'science' is totally misplaced here. Bro-science, yes.
Fonzyyy21
Well-Known Member
Do some research yourself.
No bro science behind it???
62-68°F is the perfect temp for the most dissolved oxygen in water. If I'm wrong and that's wrong information. Damn I wonder why my plants are still growing and looking perfect.
Don't tell me I'm wrong and it's bro science before you've even done research.
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Keesje
Well-Known Member
OK, then answer some questions: What is the difference in the amount of DO in water of 68 degrees and of 77 degrees?
Why don't you give your plants water of 55 degrees?
How much O2 do roots absorb per hour?
How much DO can a rez or DWC tote contain?
What are the ideal temperatures for roots?
Which kind of root rots occur at low temperature and which one at a higher temperature?
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Fonzyyy21
Well-Known Member
To much oxygen or to little oxygen causes root stunting
Again too much oxygen and cold temperatures on roots will stunt growth
Oxygen uptake is going to differ on any plant??? Big roots/big plant =more oxygen uptake that's kind of a silly question lol
Your res is gonna hold as much DO as you put in. Tapers off around 14mg/l that's about the max you put any colder water your roots will freeze and your plant wont grow.
Again 62-68°F is the perfect ideal zone. Over 72 DO dips to low.
Phytophthora occurs at lower temps and Pythium occur at higher temps.
Next time do your own research bud!
Idk where you got your facts from. Idk how res water over 70°F is bad. (Sure not ideal) Again I've got a DWC going no chiller and my water reaches up to 72° nothing wrong with my girls!
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Keesje
Well-Known Member
It is clear you just repeat what is written all these years on cannabis forums.
OK, let me enlighten you as you refuse to give answers.
Roots don't know if there is too little or too much DO in the water. Roots absorb O2 molecules and are not aware if this molecule is coming from a lot of DO or just a little. Of course when there is too little DO, then at a certain moment there are no molecules that can be absorbed. But this can happen in both cold water as in warm water.
It is true that cold water can stunt growth, but there is no relation between how much O2 is available per se.
Roots of most plants that can be grown in greenhouses and such (also cannabis) are using around 200 mg of O2 per hour per kilo of roots.
Although by itself it is true that water of a certain temperature can contain a maximum amount of DO, it is also a fact that the moment your roots absorb some of that DO, the oxygen in the rez is replenished. Simply by atmospheric pressure. So the amount of DO in a rez is endless.
It is a common mistake that people think that if you have a rez of 100 liter with a temperature of 68 °F , that it can hold only 100 x 9.2 mg of DO = 920 mg of DO.
Totally wrong. It can never exceed the amount of 920 mg at any moment. But that is not the same.
If there is 920 mg in your rez and your roots absorb 100 mg of this, then the not so educated people think that there is only 820 mg left.
"And that is why cold water is better"
But the scientific facts show us that after the roots absorb the DO, the DO level will be around 920 in the rez again. Simply by the never ending supply of O2 through atmospheric pressure.
So even if your roots are in warmer water, it makes no difference.
At 77 ° F it is 8.4 mg's and that is plenty of DO.
At 86 °F it is still 7.6 mg's. So when your rez is a 100 liter the amount of DO can never exceed 760 mg. But when the roots absorb 100 or 200 mg, a moment later there will be 760 mg of DO in your rez again.
Of course when the temperatures become really high, or if you have too much roots in a DWC that is too small, or if you have a tote that is deep and with a small surface, it can lead to problems. Then there is simply not enough time to 'refill' the amount of DO.
The 'ideal zone' is much wider as your 6 degrees. It is for most cultivated plants - including cannabis - between 66 and 80.
For lettuce and tomatoes it is around 77 degrees (according to Cornell University). For spinach it is 72.
Why would the laws of biology and physics not apply to cannabis? For sure every plant has it's own 'ideal temperature' and with cannabis even every strain. But the members of the bro-science brotherhood come up with their own facts.
As long as you supply your roots with enough DO, then the higher the temperature, the better your plants will do. Don't overdo it of course.
Although some strains of cannabis grows perfectly well in soil of 84 degrees. And the basic structure of a plant on DNA level does not certainly change when it is grown in hydro.
It is a scientific fact that metabolism works better at higher temperatures. (That is also the reason why some root rots do better at higher temperatures)
As explained before, at 72 DO will not dip too low. As long as you 'refill' with fresh DO.
The mantra of cannabis growers 'low temperature prevent root rot' is just to simplistic.
There is not 1 cause for root rot. There are several kind of root rots.
Even commercial growers sometimes don't know what causes root rot in their systems. And many of them look the same for the naked eye.
What they do is have the fungus or rot analyzed. DNA analysis. So when they know what disease they have, they can change the growing circumstances to prevent that specific disease; Lowering the temperature or making it higher, a more stable EC, making sure their feeding water is already on a higher temperature, etc.
OK, let me enlighten you as you refuse to give answers.
Nonsense.
Roots don't know if there is too little or too much DO in the water. Roots absorb O2 molecules and are not aware if this molecule is coming from a lot of DO or just a little. Of course when there is too little DO, then at a certain moment there are no molecules that can be absorbed. But this can happen in both cold water as in warm water.
It is true that cold water can stunt growth, but there is no relation between how much O2 is available per se.
No, it is not. Only for those who don't know science.
Roots of most plants that can be grown in greenhouses and such (also cannabis) are using around 200 mg of O2 per hour per kilo of roots.
Again, you don't understand it.
Although by itself it is true that water of a certain temperature can contain a maximum amount of DO, it is also a fact that the moment your roots absorb some of that DO, the oxygen in the rez is replenished. Simply by atmospheric pressure. So the amount of DO in a rez is endless.
It is a common mistake that people think that if you have a rez of 100 liter with a temperature of 68 °F , that it can hold only 100 x 9.2 mg of DO = 920 mg of DO.
Totally wrong. It can never exceed the amount of 920 mg at any moment. But that is not the same.
If there is 920 mg in your rez and your roots absorb 100 mg of this, then the not so educated people think that there is only 820 mg left.
"And that is why cold water is better"
But the scientific facts show us that after the roots absorb the DO, the DO level will be around 920 in the rez again. Simply by the never ending supply of O2 through atmospheric pressure.
So even if your roots are in warmer water, it makes no difference.
At 77 ° F it is 8.4 mg's and that is plenty of DO.
At 86 °F it is still 7.6 mg's. So when your rez is a 100 liter the amount of DO can never exceed 760 mg. But when the roots absorb 100 or 200 mg, a moment later there will be 760 mg of DO in your rez again.
Of course when the temperatures become really high, or if you have too much roots in a DWC that is too small, or if you have a tote that is deep and with a small surface, it can lead to problems. Then there is simply not enough time to 'refill' the amount of DO.
Wrong. 62 is near 'too low'. There are not many cultivated plants on earth that do well with this temperature.
The 'ideal zone' is much wider as your 6 degrees. It is for most cultivated plants - including cannabis - between 66 and 80.
For lettuce and tomatoes it is around 77 degrees (according to Cornell University). For spinach it is 72.
Why would the laws of biology and physics not apply to cannabis? For sure every plant has it's own 'ideal temperature' and with cannabis even every strain. But the members of the bro-science brotherhood come up with their own facts.
As long as you supply your roots with enough DO, then the higher the temperature, the better your plants will do. Don't overdo it of course.
Although some strains of cannabis grows perfectly well in soil of 84 degrees. And the basic structure of a plant on DNA level does not certainly change when it is grown in hydro.
It is a scientific fact that metabolism works better at higher temperatures. (That is also the reason why some root rots do better at higher temperatures)
As explained before, at 72 DO will not dip too low. As long as you 'refill' with fresh DO.
Here you are right. The ideal temperature for Pythium for example is 68 degrees. But Pythium can be heavily triggered by changing EC's as well.
The mantra of cannabis growers 'low temperature prevent root rot' is just to simplistic.
There is not 1 cause for root rot. There are several kind of root rots.
Even commercial growers sometimes don't know what causes root rot in their systems. And many of them look the same for the naked eye.
What they do is have the fungus or rot analyzed. DNA analysis. So when they know what disease they have, they can change the growing circumstances to prevent that specific disease; Lowering the temperature or making it higher, a more stable EC, making sure their feeding water is already on a higher temperature, etc.
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Fonzyyy21
Well-Known Member
Lol please show me who I copied or even what site. I looked up and did my own research bud.
You say nonsense about water temp. Relating to DO??? what are you even talking about there's been experiments done. Look at the graph. There's definitely a relation to the water temp...... but okay... whatever you say man!
Then you wanna say that bigger roots/bigger plants don't take up more O2?! But then you say they take up about 200mg of 02 per hour per kilo of roots........
Sooooo a bigger root mass does take up more oxygen!!! You literally just contradicted yourself.
"Although by itself it is true that water of a certain temperature can contain a maximum amount of DO, it is also a fact that the moment your roots absorb some of that DO, the oxygen in the rez is replenished. Simply by atmospheric pressure. So the amount of DO in a rez is endless".......
Didn't I say the res holds as much DO as you put in?! You don't even read and then wanna tell me I'm wrong lmao.
Please explain to me how 62° is to low when your plants should be around 60-65°F at night?!
You asked ideal. AGAIN 62-68° is optimum. Yeah you can have higher temps I just said that! It's not ideal and DO dips to low at higher temps.
And I don't think you understand the concept of DISSOLVED oxygen. Yeah sure go ahead and add ass much oxygen to your hot ass 80°F water, but guess what the oxygen WILL NOT be dissolved and not be available for your roots.
Hey sounds like you got it all figured out though man! Do as you please!
But I'm not wrong and didn't copy any forums or bro science lmao.
You're absolutely wrong in trying to call me out and then contradict yourself in every post!
Fonzyyy21
Well-Known Member
Soooooo you're wrong and I showed you you're wrong and I'm stupid.....
Okayyyyy!
Like I said bro a thousand times fucking read!!!!! I'm not saying there's no O2 in water at higher temps.........
I'm saying that for plants the optimal temp for the best DO is 62-68°
Damnn I'm surprised it's 100 degrees out and you're still living...
Keesje
Well-Known Member
Ok, then please explain what you meant with ....
Perhaps I misunderstood. But you clearly state that it is not possible that oxygen can be dissolved in water of 80 F.
Fonzyyy21
Well-Known Member
For plants buddyyy!!!! For plants!!!! Yeah there will be some oxygen but there won't be ENOUGH oxygen for your roots! You do as you want though and kill your plants...
Fonzyyy21
Well-Known Member
Yoooo and if you actually looked at the info and the graph I posted water has O2 all the way up until 140° but again! O2 levels will be low!
You're right can't fix stupidity or someone who doesn't wanna learn or admit that they're wrong lmao
Show me your roots at 80°F
Keesje
Well-Known Member
Of course there will be enough for your plants!
At 80 degrees there will be about 8 mg of DO per liter.
That is only about 1.2 mg less per liter then at 68 degrees.
So first of all, that is not a huge difference.
Agree or not?
Secondly, the moment the roots absorb some of that DO, their will be immediately new DO because of atmospheric pressure.
Agree or not?
And I don't grow in 80, but that is beside the point. But I know enough people who don't care if temperatures get up that high.
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Fonzyyy21
Well-Known Member
Okay fair enough not a huge difference.
But did you not ask for OPTIMAL conditions.....
And that all has to do with where you live my guy. You want to talk about atmospheric pressure you need to say above or below sea level that this works, because if you're below sea level and pressure is increased you actually have even less DO.....
If you wanna get scientific
Keesje
Well-Known Member
68 is not optimal. Optimal is a wide range, because there will be always enough DO.
I don't know the exact optimal root temperature for every strain of cannabis, because there is not a lot of research done in that field.
But as long as you keep the temperature between 64 and 80, you are ok.
70 and 74... great.
The beauty is that absorbed oxygen is refilled on the spot. So there will be always more DO available then the roots can absorb.
There are not many places on earth that are so low below sea level that you would notice a difference.
I live below sealevel and no problem at all.
I regularly visit a greenhouse that uses huge bassins for hydroponics with floating vegetables, herbs, plants.
They are experts in their field and have a turnover of millions.
In the extremely hot summers (for my country at least) of 2018 and 2019 the temperature in these bassins was way over 77 degrees.
No problems at all. They even did not do something extra to make the water move (normally they run a pump every hour or half hour for 5 minutes.
I don't know the exact optimal root temperature for every strain of cannabis, because there is not a lot of research done in that field.
But as long as you keep the temperature between 64 and 80, you are ok.
70 and 74... great.
The beauty is that absorbed oxygen is refilled on the spot. So there will be always more DO available then the roots can absorb.
There are not many places on earth that are so low below sea level that you would notice a difference.
I live below sealevel and no problem at all.
I regularly visit a greenhouse that uses huge bassins for hydroponics with floating vegetables, herbs, plants.
They are experts in their field and have a turnover of millions.
In the extremely hot summers (for my country at least) of 2018 and 2019 the temperature in these bassins was way over 77 degrees.
No problems at all. They even did not do something extra to make the water move (normally they run a pump every hour or half hour for 5 minutes.
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