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Article 5-4 Q's Liquid Caron & Gas

By Bill Lermer

Animals intake oxygen, and exhale carbon dioxide. CO2 is composed of carbon and oxgyen, but plants use far more carbon than oxygen. This is why plants intake carbon, but exhale oxygen. Plants combine carbon with water and fertilizer to produce phosphatides and sugars, two major components of flowers and leaves. It is possible for animals to obtain oxygen in a liquid, rather than a gas. It is also possible for non-aquatic plants to obtain carbon in a liquid instead of a CO2 gas.

Consider the advantages of supplying the carbon along with the nutrient solution, compared to supplementing CO2 in a gas:

With liquid carbon:

  1. 40-80 carbon atoms per molecule.
  2. No equipment is needed (saving $475-$1275).
  3. Vented rooms would not vent out supplemented CO2.
  4. Other complex organic molecules, such as hormones, sugars and flavor enhancers, can be directly absorbed, whole, by roots.
  5. The direct absorption of organic molecules (identical to normal plant content) is more efficient than first breaking down, then re-assembling.

With CO2 gas systems:

  1. only 1 carbon atom per molecule
  2. According to the Natural Gas Association, CO2 supplementation involving a propane or natural gas flame in a home is unsafe. In the event of a pilot light failure, flammable gas could combine with ambient oxygen, which, if ignited, would result in a fuel-air explosion of large force. Also, CO2 and CO (carbon monoxide) could build up to toxic levels in the event of a ventilation failure.
  3. Bottled CO2 involves lugging bottles of significant weight.
  4. It is difficult to maintain very high CO2 levels that go with the four ( 4) month bloom method (sea of green, next generation). The very high (up to 5000 ppm) CO2 levels are warranted because of the very low (down to 30%) humidity levels required because of the increased danger of mold. (Low humidity tends to close leaf pores.)

The liquid carbon method has been field-tested for years by many growers. The results have been mostly positive, but a few have reported little difference. All the growth factors work together, so a problem in one area can hold back growth. However, the liquid carbon will compensate for low light levels, because energy is injected directly into the plant. Other factors include temperature, humidity, type of medium, and nutrients. My "Optimum Candelabra Methods" article discusses a synergistic system. (It is available online at: If you have any questions, you may reach the author at that website.)

The nutrient value of soil comes from composted animals, animal waste, plants, and minerals. Since the root cells cannot ordinarily and readily absorb complex organic molecules, bacteria and enzymes are normally necessary to break down the material into the atomic form. It is then absorbed by the roots and re-assembled inside the plant. However, the liquid carbon will fuse with the roots through a process known as cellular transfection. This means that complex organic molecules suspended in the water are injected whole into the roots. This is different from the traditional method, which breaks down the nutrients and reassembles them inside the plant. It is best if the plant absorbs material through both traditional and transfection methods.

Anytime a grower switches to a different method, prudence suggests experimenting with a few plants at first. The primary caution with the earlier liquid carbon methods is that there is a need to compensate for the organic fertilizer in real soil, which is normally only slowly released, but is now instantly available.

Plant leaves are about 30% sugar, so using the liquid carbon method with sugars by-passes the normal energy consuming method. Other types of sugars can be added for more and different flavor enhancement. For example, blackstrap molasses, cherry or grape juice concentrate, etc. Citric juices should probably be avoided, due to the pulp and acidity.

There are two different types of Carbon Max, one with growth hormones and one with bloom hormones. You can also add more hormones from other sources, like seaweed which contains growth hormones. It is advisable to discontinue growth hormones the last three weeks (late bloom).

The pH of the nutrient solution in hydroponics is interesting. Generally, the best pH for the bloom stage is about 5.8; the veg stage, about 6.0-6.4. If you should find it necessary to adjust the pH, you should be aware that it takes a while for the pH to change because of the buffering of the organic molecules like the phosphatides and sugar. Carbon Max has a pH stabilizer which minimizes pH drift for about three days, when the nutrient solution should be changed.

If the pH drifts toward acid,. potassium carbonate is good to add. Potassium hydroxide will absorb carbon dioxide and become potassium carbonate, causing the pH to drift. If you have potassium carbonate and ammonium phosphate in your fertilizers, there are some side benefits. The potassium will tend to combine with the phosphorous, and the ammonium will want to combine with the carbonate. Ammonium carbonate is a pH neutralizer: ammonium will combine with acids, releasing carbon dioxide; and carbonate will combine with alkalines, releasing ammonium.

With CO2 supplementation, there is an additional advantage to using ammonium phosphate. CO2 interferes with the absorption of nitric acid, but does not interfere with ammonium. Nitric acid and ammonium are both especially useful during the growth phase.

It is especially desirable to add oxygen when using organics. Oxygen is benefical to the plant root zone for many reasons. It is important to keep down anaerobic bacteria and fungus. Chemicals can very quickly produce organics in the presence of light and water. The hydrogen peroxide is dissipated within 24 hours, so it should be replenished daily in a hydroponic system. If you put a lot of hydrogen peroxide in at a time, it can lead to floating clumps of rockwool and other organic material, and can also cause air lock in pumps with algae. A better method would be to put a siphon hose with a valve into a gallon of peroxide on a shelf above the hydro system, dripping the H2O2 into the nutrient solution.

If using drip irrigation or aeroponics, I would suggest using a good water filter attached to the pump which supplies the nutrient water. It would be ideal to not recirculate the nutrient water; if this isn't possible, change the nutrient solution every three days. You may want to collect rain water in used 55-gallon plastic drums, for the high water quality and lower water bill. It is also good to maintain a water temperature of about 72°F, to increase solubility. The water will tend to be cooler than the air, because the evaporated water will transport the heat.

It is ideal to use both liquid carbon and CO2 If you use only one method, the liquid carbon is preferred.

A few years ago, a Jesuit University asked me if some of my articles could be re-printed on CD-ROMS for use in educating future astronauts and others on high tech growing methods. I said OK, but that I needed to update them. Scholastics tend to view knowledge as almost static, and focus on minor improvements at the margin. Quantum leaps forward are usually achieved by outsiders and entrepreneurs.

The benefits of the liquid carbon method for space exploration are staggering. If the CO2 is raised to optimum levels for the plants, it would be too high for the humans. I suspect that the humans in a space station would not be able to exhale enough CO2 to support the amount of plant material necessary to provide all the food. It would also be useful for growing on thin-air low-light Mars. So I would advise future farmers in the sky to check out the liquid carbon method.

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