What types of microbes might you see under a microscope in compost tea?

To maximise the benefit of your compost tea brew, it is important to assess the quality and suitability for the purpose at hand, by establishing the type and levels of the desired soil biology.
A suitable microscope allows you to ensure that the tea has an adequate number of the appropriate microorganisms and is safe for application.
The XSZ-107T microscope not only meets but exceeds the minimum specifications needed for viewing soil biology from compost tea brewing with ease and comfort.
Assessment of compost tea is recommended to be undertaken at regular intervals of about six hours to monitor the progress until brewing is completed. It is important to check the tea immediately prior to application.
The desirable types of organisms you might see in a successful brew include bacteria, fungi, and protozoa.
You might also see algae and possibly nematodes and microarthropods like water fleas. The Compost Tea Brewing Company`s Microbes identification chart is a recommended resource.
Bacteria are tiny and will often be jiggling in the solution. We might see round, oval, or rod-shaped bacteria and these are likely to duplicate every 20 minutes under the right conditions. Spirochetes or spiral shaped bacteria moving in the tea are undesirable.

Rod Bacteria

Fungi in compost tea may be clear or coloured. Fungal spores are often dark in colour and round, oval or cigar shaped and may develop into a new organism.
Branched Fungi
Clear Fungi
Fungi with Septa
Juvenile fungi may be more prevalent and are usually wider with a bulbous end where they have emerged from the spore.
Testate Amoeba
Protozoa in the form of testate amoeba and flagellates can be expected. Flagellates will be bumbling around and range in size from 5-20 microns in diameter. Testate amoebae are egg shaped with a flat end and nucleus.
Another type of protozoa, the ciliate, can be seen in tea that has become anaerobic.
Cocci Bacteria
These can be seen at 4X magnification and will be seen moving quickly across the field of view. With reduced oxygen content in the tea, rotifers and the beautiful dancing, stalked vorticella become more prevalent. Anaerobic teas are not suitable for application to plants.
To view the soil biology in your compost tea, use your 4X objective to scan the sample for movement and larger organisms such as nematodes, rotifers and vorticella.
Identification of bacteria, fungi and protozoa can be made and/or confirmed by raising the magnification using the 40X objective.
Amoebae, nematodes, fungi and rotifers are more likely to be seen at the lower depths within the sample (i.e. closer to the top of the slide) whereas bacteria will be seen throughout the sample and flagellates are likely to cruise closer to the bottom of the cover slip.
Compost tea brewing provides a way to significantly boost soil biology and the best microscope to assess this will be one that allows for the identification of microbes discussed above.

Our recommended microscope and camera combination for soil biology:

The XSZ-107T Soil Biology Microscope not only exceeds the minimum specifications needed for viewing soil biology from compost tea brewing with ease and comfort but also provides numerous advantages mentioned above.

This microscope meets and exceeds the specifications recommended by Dr Elaine Ingram for soil microbiology.

Microscope Bundle Includes:

XSZ-107T Trinocular Microscope
Optico GT5 - 5 Megapixel Digital Camera
ToupTek Eyepiece Tube C-Mount Adapter
Soil Testing Kit


  • Viewing Head: Sliding Trinocular Head

  • Eyepieces: Wide Field Eyepiece WF10×/18

  • Objectives: Achromatic 4×, 10×, 20x, 40×

  • Nosepiece: Quadruple Nosepiece

  • Stage: Double Layers Mechanical Stage 140X140mm/ 75X50mm

  • Condenser: Abbe NA1.25 with Iris Diaphragm up & down

  • Focusing System: Coaxial Coarse and Fine Adjustment

  • Illumination: LED Illumination, Brightness Adjustable

  • Aluminium Carrycase now available as an optional accessory

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