Keesje
Well-Known Member
It is hard discussing with people who can not explain themselves well.
Also if someone calls pebbles inert and hydroton not inert... what can I say?
As explained before, the amount of oxygen is about 8.83 miligrams per liter at 72 degrees Fahrenheit.
Plant roots use 0.2 mg per hour per gram of living root.
So let's say that you have 1000 grams of roots, that means that the roots absorb 200 mg of oxygen per hour.
In DWC that is achieved by constantly aereating the water. The roots absorb the oxygen and because of the agitation of the surface the water picks up new oxygen from the air. This happens really fast and really easy.
Because the moment your roots absorb the oxygen, the dissappeared oxygen is supplemented from the air. It has to do with air-pressure. It happens automatically.
The difference between 8,83 grams per liter or 7.2 grams per liter does not matter that much. Once the roots absorb it, it is filled up again immediately. And again. And again. There will always be more oxygen available then the roots can absorb.
As long as the contact of the water with surrounding air is ok, it will be fine. No matter if you do this with flooming, waterfalls, bubbles, it is al good. Even if you would do nothing, oxygen would go in water, just because of airpressure in the atmosphere.
Of course there are limits. If yoy heat up the water a lot, or your container is really small compared to the rootmass, then things will go wrong.
In Ebb & Flow you achieve that necessery amount of oxygen in another way.
You fill your container up with water. Some oxygen will come with the water, but more then 90 % of the oxygen will come after the water has left. The roots are still wet, and are surrounded by air, rich with oxygen. Those are the ideal circumstances for roots.
That is why roots grow well in airy soil or rockwool. Moist surroundings, not saturated and plenty of air. Nobody in his right mind who grows in soil or rockwool would give water that is aerated.
Aerating your water in the reservoir before pumping it in your Ebb & Flow container is also useless and nonsense. First, there is already DO in the water while it is in the reservoir. It will also pick up the maximum amount of oxygen anyway when you pump in the container. But most importantly, the roots will absorb the majority of the oxygen after the water has left, as explained before.
Recirculating your reservoir now and then, is not uselesss. It makes sure that the nutrients are eveywhere and the temperature is more evenly in the reservoir. But for aerating.... useless.
Also if someone calls pebbles inert and hydroton not inert... what can I say?
Ok, let me try to educate you a little.My point with NitroFii is that a small change in adding more nitrogen has a huge impact , so while you suggest that the small change in water storing oxygen at lower temps is insignificant,, based on what.. your impression/interpretation, your intimate knowledge of physics?
As explained before, the amount of oxygen is about 8.83 miligrams per liter at 72 degrees Fahrenheit.
Plant roots use 0.2 mg per hour per gram of living root.
So let's say that you have 1000 grams of roots, that means that the roots absorb 200 mg of oxygen per hour.
In DWC that is achieved by constantly aereating the water. The roots absorb the oxygen and because of the agitation of the surface the water picks up new oxygen from the air. This happens really fast and really easy.
Because the moment your roots absorb the oxygen, the dissappeared oxygen is supplemented from the air. It has to do with air-pressure. It happens automatically.
The difference between 8,83 grams per liter or 7.2 grams per liter does not matter that much. Once the roots absorb it, it is filled up again immediately. And again. And again. There will always be more oxygen available then the roots can absorb.
As long as the contact of the water with surrounding air is ok, it will be fine. No matter if you do this with flooming, waterfalls, bubbles, it is al good. Even if you would do nothing, oxygen would go in water, just because of airpressure in the atmosphere.
Of course there are limits. If yoy heat up the water a lot, or your container is really small compared to the rootmass, then things will go wrong.
In Ebb & Flow you achieve that necessery amount of oxygen in another way.
You fill your container up with water. Some oxygen will come with the water, but more then 90 % of the oxygen will come after the water has left. The roots are still wet, and are surrounded by air, rich with oxygen. Those are the ideal circumstances for roots.
That is why roots grow well in airy soil or rockwool. Moist surroundings, not saturated and plenty of air. Nobody in his right mind who grows in soil or rockwool would give water that is aerated.
Aerating your water in the reservoir before pumping it in your Ebb & Flow container is also useless and nonsense. First, there is already DO in the water while it is in the reservoir. It will also pick up the maximum amount of oxygen anyway when you pump in the container. But most importantly, the roots will absorb the majority of the oxygen after the water has left, as explained before.
Recirculating your reservoir now and then, is not uselesss. It makes sure that the nutrients are eveywhere and the temperature is more evenly in the reservoir. But for aerating.... useless.