Does Barley Kill Algae?


Dear Frog,

We gotta get busy, spring is just three weeks away. It is time to think about pond plants. It is time to think about aeration. It is time to consider the weeds. Whoa! Hold on. Let us use a little science.

You cannot expect to do any one thing to make a complex system like a pond work but you can work on the system. A pond is a closed system where if you are missing something Mother Nature will supply it. However, you can improve on the eco-system. A natural system takes around 10,000 years to establish. I don’t have the time. I can do it in three years because I can fetch and carry.

First, consider respiration. Plants do this in nature and so will we. However, to get started we are going to have to take care of this. Fountains do not work. Nor do water falls. The reason you grow weeds and algae is because the pond is full of fertilizer. What kind of fertilizer? When fully decomposed: gasses. Carbon dioxide, ammonia, hydrogen sulfide, and methane are great fertilizers; and except for methane are much heavier than water. How do we remove them?

This is a recipe. Use barley straw; it works best. Loosely packed barley straw in burlap or onion bags place at the shore half in and out of the water will ferment. This lowers the pH of the pond so sex cannot happen (no algae reproduction) and also gives a habitat for algae predators. And barley straw is so sweet it acts as a great medium for organic decomposers that form the organic gasses. And there is reason to believe barley straw works as a bioside (beneficial killer).  However, alone, barley doesn’t work.

The second ingredient is pond bacteria. Any organic matter such as leaves will decompose in the pond. However, this is a slow process unless you seed the pond with pond bacteria. There are several species when introduced into the pond will completely degrade the leaves to the basic organic heavy gasses.

The power for all of these ingredients is the aerator. You cannot remove the gasses in the pond by moving water. If you pump diffused air to the bottom of the pond, the heavy pond gasses will be lifted out of the pond. The reason they are remove is due to a basic gas law (Boyle) that operates the entire planet. The partial pressures and volumes of miscible gasses in water must equilibrate. If you pump air (nitrogen and oxygen) into the bottom at the deepest point, out pops the heavy fertilizer gas: no weeds.

Breathe easy Glug. It will be nice catching a springtail soon.
PonDoc from the pond

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