Hello,
I have been reading a lot lately about people now using fine CO2 mist (mazzei, etc.) to increase plant growth versus having the CO2 completely dissolved in the water. It has been said that the plants can grow faster and the aquarium dissolved oxygen levels will be higher with a mazzei type of setup compared to a reactor that has a 100% dissolve rate. The higher dissolved oxygen levels indicate increased photosynthesis occurring when all other factors involved in plant growth remain the same. It has been said that these benefits are also achieved while using less CO2 than with a highly efficient reactor.
I have never used a mazzei setup to test any of this for myself, but it has brought something to my mind that I can't stop thinking about.
My question is that if you can get a boost in plant growth just by blowing a fine mist of CO2 bubbles around versus fully dissolving the CO2 in the water, why couldn't you achieve most of the same benefits by just blowing around a fine mist of air in the tank instead of pure CO2? Air already has a much higher concentration of CO2 in it (380ppm or so) than the fish in our tank water could ever handle in a dissolved state. This would completely eliminate the need for CO2 tanks, regulators, solenoids, etc. You would mist the tank with micro air bubbles and the plants would get their CO2 from those bubbles directly. Then the tank would also never have fish kills from CO2 accidents, the aquarium would never have too little oxygen for the fish at night, drop checkers/pH probes, etc. would become unnecessary, you wouldn't have to worry about CO2 outgassing in your filter designs at all, etc. Just run something like a mazzei with a high enough pressure so it can create a super fine mist of microbubbles and then run air through it.
It seems to me like the only problem with airstones and venturi's on powerheads is that they make bubbles that are too large to ever make it down to the plants to stick to them and give the plants their CO2. As a result, they instead just end up outgassing the tank's dissolved CO2 (anything over natural equilibrium with air) and don't benefit the plants at all by having the bubbles stick to the leaves to give the plant atmospheric CO2.
Tom has also talked about the boundary layer on the plant's leaves as well, and mentioned how the boundary layer on terrestrial plants is much lower than on aquatic plants. Wouldn't the boundary layer also be lessened substantially then with a bubble hitting a leaf directly and creating an air/leaf interface between the bubble and leaf instead of a water/leaf interface?
Is there something that I am missing having to do with understanding how CO2 interacts with the plants to make these questions null and void?
I don't necessarily think that this setup would get you all the growth of a CO2 only mazzei since each bubble in the tank would have less CO2 to give the plant when stuck to it, but it might possibly easily get you something in-between a CO2 injected tank and a natural "walstad" type of tank growth level. I am thinking somewhere around Excel levels of growth without needing Excel at all.
I just don't have any way to try this right now with my current setups in order to test this for myself, so I thought I would throw it all to you guys and ask for your two cents/experience.
Have a good one, Jeremy
I have been reading a lot lately about people now using fine CO2 mist (mazzei, etc.) to increase plant growth versus having the CO2 completely dissolved in the water. It has been said that the plants can grow faster and the aquarium dissolved oxygen levels will be higher with a mazzei type of setup compared to a reactor that has a 100% dissolve rate. The higher dissolved oxygen levels indicate increased photosynthesis occurring when all other factors involved in plant growth remain the same. It has been said that these benefits are also achieved while using less CO2 than with a highly efficient reactor.
I have never used a mazzei setup to test any of this for myself, but it has brought something to my mind that I can't stop thinking about.
My question is that if you can get a boost in plant growth just by blowing a fine mist of CO2 bubbles around versus fully dissolving the CO2 in the water, why couldn't you achieve most of the same benefits by just blowing around a fine mist of air in the tank instead of pure CO2? Air already has a much higher concentration of CO2 in it (380ppm or so) than the fish in our tank water could ever handle in a dissolved state. This would completely eliminate the need for CO2 tanks, regulators, solenoids, etc. You would mist the tank with micro air bubbles and the plants would get their CO2 from those bubbles directly. Then the tank would also never have fish kills from CO2 accidents, the aquarium would never have too little oxygen for the fish at night, drop checkers/pH probes, etc. would become unnecessary, you wouldn't have to worry about CO2 outgassing in your filter designs at all, etc. Just run something like a mazzei with a high enough pressure so it can create a super fine mist of microbubbles and then run air through it.
It seems to me like the only problem with airstones and venturi's on powerheads is that they make bubbles that are too large to ever make it down to the plants to stick to them and give the plants their CO2. As a result, they instead just end up outgassing the tank's dissolved CO2 (anything over natural equilibrium with air) and don't benefit the plants at all by having the bubbles stick to the leaves to give the plant atmospheric CO2.
Tom has also talked about the boundary layer on the plant's leaves as well, and mentioned how the boundary layer on terrestrial plants is much lower than on aquatic plants. Wouldn't the boundary layer also be lessened substantially then with a bubble hitting a leaf directly and creating an air/leaf interface between the bubble and leaf instead of a water/leaf interface?
Is there something that I am missing having to do with understanding how CO2 interacts with the plants to make these questions null and void?
I don't necessarily think that this setup would get you all the growth of a CO2 only mazzei since each bubble in the tank would have less CO2 to give the plant when stuck to it, but it might possibly easily get you something in-between a CO2 injected tank and a natural "walstad" type of tank growth level. I am thinking somewhere around Excel levels of growth without needing Excel at all.
I just don't have any way to try this right now with my current setups in order to test this for myself, so I thought I would throw it all to you guys and ask for your two cents/experience.
Have a good one, Jeremy