How to Make a DIY Monotub Mushroom Growing Kit

A step-by-step guide to building your own monotub mushroom growing kit using a filtered tub, substrate and simple setup methods.

A DIY monotub mushroom growing kit is a popular option for growers who want more control over their setup. Instead of buying a complete kit, you build your own system using a tub, filters and growing materials.

This approach is ideal for users who want flexibility, reusable equipment and a deeper understanding of how monotub systems work.

👉 Browse Monotub Kits & Equipment

DIY Monotub Setup Overview

• Use a plastic tub (25L or 45L is a great starting point)
• Add filtered airflow holes
• Prepare and add substrate
• Maintain a stable environment

What You Need to Build a DIY Monotub

• Plastic storage tub (25L or 45L)
• Filter material or self-adhesive filters
• Substrate or growing medium
• Clean working environment

👉 Ready-made option: Empty Monotub with Filters 45L

Step-by-Step DIY Monotub Setup

1. Choose Your Tub Size

Select a 25L tub for smaller setups or a 45L tub for larger capacity. Larger tubs provide more internal space but require more environmental control. Taller tubs can also help reduce condensation dripping from the lid.

2. Add Airflow Holes and Filters

Add 6 x 50mm holes for airflow:

• 2 holes on the front and 2 on the back (approx. 4 inches from side walls and 3.5 inches up from the base)
• 1 hole on each side (approx. 0.5 inches from the rim)

Proper airflow is essential. You can drill holes using a hole cutter — spinning the cutter in reverse can help melt the plastic slightly, reducing the risk of cracking.

Add filter material such as polyfill, or use self-adhesive monotub filters (e.g. 50x70mm).

👉 Add a black plastic liner to the base of the tub to reduce side pinning and improve consistency.

3. Prepare Your Growing Medium

Prepare your substrate ready to mix, or use a pre-prepared all-in-one monotub bag option. Ensure it is evenly distributed within the tub.

👉 View Monotub Kit with Substrate Options

4. Set Up Your Environment

Place your monotub in a stable environment with consistent temperature, airflow and cleanliness. Around 22–23°C is ideal for monotub setups. If using a heat mat, set it accordingly to maintain this range.

👉 Read Environment Guide

5. Monitor and Maintain

Check conditions regularly without over-handling the tub. Stability is key to a successful setup.

DIY Monotub vs Pre-Built Kits

Related Guides

👉 How to Use a Monotub Kit
👉 Monotub vs All-in-One
👉 General Growing Guide

Frequently Asked Questions

Is it better to build a DIY monotub?

DIY monotubs offer more control and flexibility, but require more setup compared to ready-made kits.

What size monotub should I use?

25L is easier to manage, while 45L provides more capacity for larger setups.

Do I need filters for a monotub?

Yes, filtered airflow helps maintain a balanced growing environment.