The quality of your compost tea maker, or brewer, will determine whether you're able to unleash the true miracle that lies within aerated compost tea. Below, we discuss some of the most important qualities that you must look for when you're in the market to purchase, or even build, a compost tea maker.
NOTE: Assessing these qualities applies to every compost tea brewer, however, since most of our visitors are backyard gardeners, we focus our attention on their specific needs.
There are two key qualities that you must look for in all compost tea brewers when your goal is to produce aerated compost tea - Aeration and Agitation.
Aeration needs to be your number one priority when looking into buying or making a compost tea brewer. Aeration refers to the ability of a brewer to produce adequate amounts of oxygen (O2) during the entire brewing cycle.
We must understand that the microbes that we want to grow in our aerated compost tea are aerobic by nature, that is, they need oxygen to survive. We don't want to breed anaerobic microbes in these teas, so we must ensure adequate O2 levels at all times.
Here's the cache - the oxygen requirements of the microbes in your compost tea change throughout the brewing cycle. As the populations increase, the microbe's need for oxygen increases dramatically. At this same time, the microbes production of carbon dioxide (CO2) starts to increase rapidly. Now you've got two factors to think about - increasing the O2 and decreasing the CO2. We'll discuss oxygen-needs first and cover carbon dioxide removal in our section below on agitation.
What is an adequate amount of oxygen?
The experts in this field recommend a total dissolved oxygen level above 70-80%% or 6 ppm.
How does oxygen enter our compost tea?
The only way oxygen can enter into water is at its surface. Therefore, you must ensure the surface tension of your liquid is consistently broken by oxygen bubbles. The method used by most compost tea brewing systems is to force oxygen into the liquid from it's base. This type of system forces bubbles upwards towards the water surface which results in a continuous breaking of the surface of the water. This continuous breakage of surface tension allows the CO2 produced by the microbes to escape and a higher level of dissolved oxygen to be retained.
How do you know if a brewer can meet this demand?
You can buy an oxygen probe OR you can buy a compost tea maker which has gone through vigorous testing and has generated proven results. The compost tea brewer below offers just that!
*Please note that both of these lab test were done on compost teas that were brewed using these complete microbe food kits.
Agitation describes the ability of your compost tea maker to extract the microbes from the physical compost matter in your tea while rendering them unharmed. You don't want to mix too vigorously or else it will kill the microbes.
Agitation also refers to a brewer's inherent ability to keep the microbe foods well mixed throughout the brewing cycle.
You can conduct this simple test to determine if the mixing-ability of your compost tea maker is sufficient.
The compost tea brewers that we sell in our store pass all of these tests with flying colors...that's part of the reason why we carry them.
This is the only 12-hour Soil Food Web approved brewer in the world. It's very easy to use and comes recommended by Dr. Elaine Ingham.
This is the same model that we started with 6 years ago for our backyard oasis.
To learn more, please visit our store.