Thinking Outside The Box

[PhatNuggz]

Equilibrium is equilibrium https://www.merriam-webster.com/dictionary/equilibrium

yes 2 disparate things (IE water chemistry and swimming pool marcite) when the calcium in the pool water is less than at equilibrium with th calcium in the marcite, it will pull the marcite from the sides, which is why people have to remarcite their pools. However, the opposite is not true. These days marcitee is not used for this reason

 

[PhatNuggz]

OK I have a fair bit of personal experience with Co2/O2 dissolution in water. I can give you my take but i'm going off pure memory and have no time to look this up for accuracy so please ensure to double check.

DO levels in water with no influence of uptake are determined by temperature, pressure and salinity. In our case temperature is the most influential. lower temps hold more oxygen. This biggest misconception people have is that you can add more oxygen to the water than it holds at equilibrium. Yes you can but oxygen is extremely hard to dissolve in water above equilibrium and there is no need to do so IMO. Our goal is to maintain DO levels as close to equilibrium so that we do not become deficient in them. These type of atomizers create the smallest of bubbles and the theory is the smaller to bubble the more oxygen this supplies because it has more surface area contact with the water. While is true the magnitude of it is very insignificant. Most airstones provide bubbles that reach the surface quickly due to size and buoyancy, atomizers can create bubbles that hang in the water column for quite some time not really increasing DO levels but the suspension of gas in the water (I cannot say if this has any benefit or consequence). The other negative side to an atomizer is the break down of the plates as it reacts (i believe this is due to oxidization but cannot remember for sure) and I believe releases heavy metals in that reaction. Whether or not toxic levels I cannot remember.

In terms of adding Co2 to the water with air pumps. This just can't happen (in most cases) because of equilibrium if your supply air source is the same as your grow space Co2 levels in the air are the same and have reached equilibrium therefore the only gas exchange that an air pump could contribute to is a dissolved gas that has been depleted below equilibrium.

The biggest factors we need to look at are in no particular order are:

1.Circulation of the water in our systems (Oxygen can become depleted at the top or bottom layer of water) so it key to our water mixing.
2. Surface area agitation. The largest portion of gas exchange happens from surface area agitation (remember you wont feasibly be able to add more DO than equilibrium but maintaining those levels is key) There are more ways than airstone and some are more effective than airstones however airstones also provide mixing of the water column.
3. Water temp to a lesser extent because as long as you have adequate surface area and agitation you should be good. (only speaking in terms of DO)

There are more but these are the main ones.

My observation combined with ancient chemistry recollection: Emitters do not add O2, they free it by breaking the H2O molecule bond down rendering the O to nano size= many-fold more surface area. The nanosized bubbles tend to stay in suspension over the more buoyant O2 molecules

 

[PhatNuggz]

There are 2 types of bacteria anaerobic and aerobic. In hydro you will never have anaerobic conditions. This usually occurs in compact substrates in nature not in water columns and those types of bacteria are responsible for h2s gas that can be deadly at low concentrations.

The temps you are quoting are shoot and leaf temps I think not the roots. I would have to see the study. Transpiration is the driving force for water uptake this takes place in the leaf and is most affected by leaf temp...not root temp. Although at some point low root temp would affect this and in the studies I have read that occurs below 66f and the growth rate from 68 to 75f is not all that significant.

then what causes root rot or root slime? I have experienced both when temps were too high

 

[Shawnery]

then what causes root rot or root slime? I have experienced both when temps were too high

Exactly my thought. My understanding is that the growth of anaerobic bacteria is what causes root rot not the heat at all. Anaerobic bacteria propagates in an environment lacking in oxygen content but high in heat and aerobic bacteria thriving in a warm environment with high levels of DO.The point, I thought, was to increase oxygen content to combat the forming of anaerobic bacteria.

I believed the point of raising the temp level while increasing oxygenation was to increase the growth of aerobic bacteria?

 

[Aqua Man]

then what causes root rot or root slime? I have experienced both when temps were too high

There are good and bad aerobic bacteria. Look at salmonella, ecoli and one that's common in hydro pythium. All of which reproduce faster in higher temps. Anaerobic and aerobic bacteria only means one requires oxygen and the other does not. It has no bearing on whether or not they are beneficial.

 

[Aqua Man]

Just add the beneficial bacteria we use from addatives such as hydrogaurd survive much better than most undesired bacteria in cold water. I'm not saying warmer temps will cause root rot.. what I'm saying is in cooler temps the outbreak will not advance as quickly and will hinder the reproduction of most of the undesired bacteria while still providing a good environment for the reproduction of desirable bacteria

 

[Shawnery]

The definition of aerobic is good and anaerobic is bad. Anaerobic bacteria is what causes the foul smell in your water.

 

[Aqua Man]

The definition of aerobic is good and anaerobic is bad. Anaerobic bacteria is what causes the foul smell in your water.

There are many causes of smell in water. Dying bacteria, bacteria breaking down organic matter both in aerobic conditions. Think about this why does rotting food smell? It's not because it's in anaerobic conditions. Like I said you will not come across anaerobic conditions in a water column. What you will see is low oxygen where it will negatively impact the plants processes. Due to that the root may suffer damage and bacteria will begin to feed on the decaying matter. Usually this is where pythium starts to take hold. And in warm temps very rapidly. I think you are a bit confused saying all aerobic bacteria are good and all anaerobic bacteria are bad. That is simply not the case.

Just going to add you leave potatoes salad out in the sun and add hi lvls of oxygen. Is this going to make it no spoil? No in hours it will be crawling with bacteria. Put it in the fridge and it lasts for days. Bacteria have optimal conditions and depending on the type it will vary. The good bacteria in products like hydrogaurd have been chosen for these purposes and will do much better in cooler water than bacteria we are trying to avoid. They do well in a wider temperature spread than most of the bacteria we are trying to avoid. Bacteria is present in our non sterile systems... but you dont see any problems until the ideal conditions are met for them. Temperature is one of those conditions and when you add some plant health issues boom you have a rapid outbreak. In cooler waters this happens much less rapidly and allows you a window of time to improve conditions. You can still get root rot and any temps that we use for hydro but the effects are far more rapid in warm water

 

[Shawnery]

From my research,

ll bodies of water possess a dynamic balance of microbiological activity. In hydroponics, we strive to keep the nutrient solution as sterile as possible, but nonetheless, nutrient solution is by its very nature the perfect place for things to grow. Some microbes require dissolved oxygen to live (aerobic), and others do not (anaerobic). As a general rule of thumb, aerobic bacteria are "good," and anaerobic are "bad." Put simply, the byproducts of anaerobic respiration are acids that wreak havoc with chemical and biological balances within the nutrient solution, which in turn harms the root system. Warm, stagnant water holds little dissolved oxygen, making it an ideal breeding ground for anaerobic bacteria, many of which (Fusarium, Pythium) cause crop failure as they take up home in the fragile root system and proliferate. The foul smells associated with warm stagnant water (sewers, swamps) is caused by these "bad" bacteria. Methane gas (swamp gas) is a highly flammable "natural" gas that is also a byproduct of anaerobic bacteria. Can you see how, left unchecked, these bacteria can ruin a crop? Rampant pH swings, swampy smells, root rot and ultimately crop failure are the tell tale signs of a poorly balanced biology within your system.


Pythium grows in anaerobic conditions

 

[Shawnery]

If we're taking your thread off-topic let me know and I'll back off? I'm interested because everything I'm reading makes me think the opposite way of Aqua.

 

[Aqua Man]

From my research,

ll bodies of water possess a dynamic balance of microbiological activity. In hydroponics, we strive to keep the nutrient solution as sterile as possible, but nonetheless, nutrient solution is by its very nature the perfect place for things to grow. Some microbes require dissolved oxygen to live (aerobic), and others do not (anaerobic). As a general rule of thumb, aerobic bacteria are "good," and anaerobic are "bad." Put simply, the byproducts of anaerobic respiration are acids that wreak havoc with chemical and biological balances within the nutrient solution, which in turn harms the root system. Warm, stagnant water holds little dissolved oxygen, making it an ideal breeding ground for anaerobic bacteria, many of which (Fusarium, Pythium) cause crop failure as they take up home in the fragile root system and proliferate. The foul smells associated with warm stagnant water (sewers, swamps) is caused by these "bad" bacteria. Methane gas (swamp gas) is a highly flammable "natural" gas that is also a byproduct of anaerobic bacteria. Can you see how, left unchecked, these bacteria can ruin a crop? Rampant pH swings, swampy smells, root rot and ultimately crop failure are the tell tale signs of a poorly balanced biology within your system.

I'm heading out for lunch. In vegas for another week or so but I will respond to this when I get back. Great conversation for learning. But you need to remember we do not have a substrate in hydro like we do in nature or some aquariums. If you just look up where anaerobic bacteria form in both nature and aquariums you will see we do not have anaerobic conditions in hydro. Some anaerobic bacteria are also tolerant of oxygen but require high co2 it's not a black and white thing and gets complex. I am not a microbioligist but a hobbiest si I will provide the info I can on it. Sometimes it's hard for me to remember the exact explanations behind all the processes.

 

[Aqua Man]

From my research,

ll bodies of water possess a dynamic balance of microbiological activity. In hydroponics, we strive to keep the nutrient solution as sterile as possible, but nonetheless, nutrient solution is by its very nature the perfect place for things to grow. Some microbes require dissolved oxygen to live (aerobic), and others do not (anaerobic). As a general rule of thumb, aerobic bacteria are "good," and anaerobic are "bad." Put simply, the byproducts of anaerobic respiration are acids that wreak havoc with chemical and biological balances within the nutrient solution, which in turn harms the root system. Warm, stagnant water holds little dissolved oxygen, making it an ideal breeding ground for anaerobic bacteria, many of which (Fusarium, Pythium) cause crop failure as they take up home in the fragile root system and proliferate. The foul smells associated with warm stagnant water (sewers, swamps) is caused by these "bad" bacteria. Methane gas (swamp gas) is a highly flammable "natural" gas that is also a byproduct of anaerobic bacteria. Can you see how, left unchecked, these bacteria can ruin a crop? Rampant pH swings, swampy smells, root rot and ultimately crop failure are the tell tale signs of a poorly balanced biology within your system.


Pythium grows in anaerobic conditions

Few min waiting for the other couple. The biggest reason you will never see anaerobic condition in hydro is the water is not stagnant, there is no substrate and thus is important because it's usually a compact substrate that causes no water to flow through it and thus the aerobic nitrifying bacteria consume the small amount of oxygen at the surface layer and just beneath the anaerobic nutrifying bacteria use a different process and give off h2s as a byproduct. Our hydro systems have more than enough flow, gas exchange to prevent any anaerobic conditions. The smell is bacteria breaking down organic matter and dying bacteria.
And absolutely not all aerobic bacteria are good. Its marketing that uses a lot of this info as half truths and lies to sell shit

 

[Aqua Man]

If you want a great source of info on water conditions. Look up Tom barr and do some reading. He has a website and is probably in the top 3 in the world dealing with planted tanks. You will easily find info on anaerobic conditions and nutrient and more than your your brain will want to handle

 

[Shawnery]

What I'm confused by is if pythium is caused by anaerobic conditions than how is there no anaerobic bacteria in the system when you get pythium?

 

[Aqua Man]

Some anaerobic bacteria can tolerate oxygen environments it's not black and white. Its opportunistic and will usually only infect plants with health issues and can range in how quickly it will multiply based on environments and other factors. It thrives in low oxygen and higher temps. Raising temps lowers overall lvls of DO and provides an ideal environment. This does not mean you will have problems with it though. What it means is if you have plant health issue like nute burn, osmotic shock etc. The likelyhood and rate at which it reproduces increases. Like I said it's not black and white

 

[Aqua Man]

What I'm confused by is if pythium is caused by anaerobic conditions than how is there no anaerobic bacteria in the system when you get pythium?

Pythium is not really caused by anything. In a living medium not sterile. You just increase risk factor and how rapidly it can reproduce. If you plant is in top top shape from seed to harvest it's unlikely you will see any problems. But increase the preferred environmental factors like temp, low oxygen and then add a bump in the road and you are a lot more likely to see pythium

 

[Shawnery]

Very long read but very much worth it!

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-54052006000400001

 

[Aqua Man]

Yes like I was saying higher temps increase the risk as do many other factor such as plant health, o2, co2, ph, anything that stresses or affects plant health. Having a higher equalibrium of DO is imo a benefit. But again you just increase the risk it's not to say it cannot be done. Also a key factor is having beneficial bacteria out compete the bad bacteria. So let's not confuse info from sterile and live environments.

 

[Aqua Man]

Copied from that study. This is why lower temps and use of hydrogaurd has proven so effective in preventing pythium. Remember there are several factors that influence the risk of an outbreak and oxygen is only one. A lot of peer studies and scientific studies show that at 68f and adequate airstones with adequate flow are sufficient. Adding atomizers imo will not eliminate the need for consideration of the other factors such as temp.

Quote

Introduction of microbial agents, manipulation of the root zone microflora, oxygenation of the nutrient solution, and regulation of nutrient solution temperature are among the best available approaches to suppressing Pythium in the root zone,

 

[Shawnery]

But bacteria do better in warmer environments from my understanding. Obviously there is a point of diminishing returns. I'm really just thinking out loud if these new emmiters will allow you to keep the DO high enough to promote beneficial bacteria and not increase the risk of let's say pythium?

The other study got double the yield from 68 to 74. Ofcourse there must be an increased factor of getting root rot or the like but if you can create an environment that combats that even with higher temps, would that not be worth it?