I wanted to activate some virgin biochar with microorganisms and nutrients before adding it to some new substrates I was formulating. Without activation I was concerned that the new biochar would rob the surroundings of it’s cations and leave the plants in the substrate with less nutrients. I also wanted to observe if the biochar was adsorbing nutrients in the tea or just absorbing the tea. So I made a tea, consecutively placed 3 sacs of virgin biochar in the tea, took samples of the tea out after every sac of biochar activated to see the difference in color of the teas. This would tell me something about what biochar was absorbing and adsorbing from the tea.


On June 23 2011 I started the procedure:

Contents of Liquid Tea

  • 8gal of coopebrisas compost and
  • 2gal of lombris humus (older),
  • 35 gal of decloronated water,
  • 1 gal of molasses,
  • 1 gal of fish emulsion,
  • .5gal MM

All were placed in a 55 gal tank and injected bubbles on the bottom for two days.


First Sac of Biochar Activated

I then added  the 1st sac of 20gal of biochar (5.5pH) with a weight on the top to hold it submerged. The sac was full. Laid flat the sac measured 60x100cm.

OBSERVATIONS – lots of bubbles after the 1st BC was in tank for one day. During the making of the tea there were really no fermentation bubbles on the top of the liquid.

I took the first sac out 2 days later.


Second & Third Sac of Biochar Activated

I added the second sac and took it out 2 days later as well.

I added a third sac but it was only 60% full (13gal) of BC otherwise it would not be able to be submerged below the liquid since much of the liquid was gone, due to the first 2 sacs absorption.

I took the 3rd sac out 2 days later as well.

After the 3rd sac was submerged for 2 days, what was left in the tank was rice hulls and a bit of more of the solid components of the Coopebrisa’s compost, the bubble tubes and approximately 10 gal of liquid tea. There was approximately 35gal to begin with. This means 25 gal of liquid was absorbed by the 53 gal of biochar in the 3 sacs.

25 gal of 53 gal = 47.2%

The Biochar Absorption of Water test calculated a 55.2% liquid absorption capacity of biochar. So this test shows a bit different water absorption capacity.


The Tea Samples Taken After Each Activation

So what I found very interesting was the difference in the coloration of the teas samples that were taken immediately after i took out each of the 3 different sacs of biochar. There was a markedly difference in the color of the teas. They progressively got lighter in color. I am hoping Gabi Soto, a BC researcher at Catie University here in Costa Rica will duplicate the experimenter noting more exact data and analyze the liquids and biochar afterwards. Activating biochar could be an important improvement for biochar use if more was known about it.