Papers & Guides
Biofilm & Microbiology
September 25, 2026

The Layman's Guide to Microbial Whatsits

Read Greg Walker’s free guide to aquarium biofilms, microbes and nutrient cycles. Explore aquatic ecology in plain English and download the PDF.

Greg Walker, Niskai Aquatics

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A note from Greg

I wrote this guide to make the less visible side of aquarium keeping easier to understand: the microbes, biofilms, nutrient pathways and quiet processes behind the glass.

That curiosity sits at the centre of Niskai. This is where I can share the thinking behind my work, explain how I see an aquarium, and give you something useful to take back to your own tanks.

Expect plain English, a few jokes, and room for complexity. My aim is to help you ask better questions and make more informed decisions about your own system.

Inside the guide

  • A closer look at the familiar nitrogen-cycle explanation.
  • Biofilms and their place in the aquarium.
  • Microbial additions, nutrient availability and the limits of test-kit readings.
  • Connections between aquariums, terrariums and paludariums.
  • A critical look at hobby myths, marketing and claims of microbial magic.

How to read it

This is an ecology-focused guide for curious fishkeepers. It is intended to sit alongside observation and hands-on experience, rather than serve as a step-by-step first-tank manual.

The introduction here is my perspective on the work. The downloadable guide contains the explanations and arguments in full, so you can consider them in context.

Get the guide

Use Open PDF above to read or save The Layman's Guide to Microbial Whatsits, version 1.0. It is freely available, with no email signup.

If you pass it on, share this page so the introduction and download stay together.

Bibliography / Recommended reading

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Support the Journal

Niskai Journal is free to read. If you found this useful, you can help support more independent aquarium work.