Cultivation supplies
by Microppose
We'll only email you about this product — no marketing.
The Microppose Monotub Liner is a custom-fitted polyethylene bag designed to line the inside of your Microppose Monotub, protecting the tub from substrate residue and making end-of-cycle cleanup a 30-second job. Sold in packs of 10, available in three sizes (Small, Medium, and Large) to match the full Microppose Monotub range.
Match your liner to your Microppose Monotub. Each liner is cut to sit flush against the base and walls of the corresponding tub size — no trimming, no folding, no guesswork.
| Liner Size | SKU | Fits |
|---|---|---|
| Small | SH0191 | Microppose Small Monotub |
| Medium | SH0198 | Microppose Medium Monotub |
| Large | SH0199 | Microppose Large Monotub |
Not sure which Microppose Monotub you've got? Check the base — the size is moulded into the plastic. If you're buying a tub and liners together, just match the size labels and you're sorted.
Here's the honest version: you can grow mushrooms in a monotub without a liner. People do it all the time. But after your first harvest, when you're chipping dried substrate off the walls with a spatula and wondering if that discolouration is contamination or just staining — that's when you'll wish you'd spent a couple of quid on a liner.
The practical problem is straightforward. As your mycelium colonises the substrate and begins fruiting, the substrate block shrinks. It pulls away from the tub walls, creating a gap. That gap is a microclimate — humid, dark, sheltered — and it's where side pins love to form. Side pins are mushrooms that fruit along the bottom and sides of your cake instead of the top surface. They're awkward to harvest, they waste energy that could go into your main canopy, and they make the whole operation messier than it needs to be.
A liner solves this because the thin plastic clings to the substrate as it contracts. No gap forms, no microclimate develops, and your pins concentrate on the top surface where you actually want them. It's not a magic trick — it's just physics. The liner also means your tub stays clean between grows. Pull out the liner, wrap up the spent cake, bin it, and your Microppose Monotub is ready for the next round without scrubbing. We've seen growers get years of use out of a single tub this way, versus the ones who go liner-free and end up with stained, scratched plastic that gets harder to sanitise with every cycle.
We'll be straight with you — some growers just cut bin bags to size and call it a day. It works, sort of. But bin bags aren't sized to your tub, so you end up with excess material bunching in the corners, creating folds where water pools and contaminants hide. You also spend 10 minutes per tub faffing about with scissors and tape when you could be inoculating.
The Microppose liners are pre-cut to the exact internal dimensions of each Microppose Monotub size. They sit flat against the base and walls with enough extra length at the top to fold over your spent cake when it's time to dispose. The plastic is thin enough to cling to contracting substrate but thick enough that you won't accidentally puncture it during spawning. It's a small detail, but when you're running 4 or 5 tubs at once, the time saved and the consistency gained adds up fast. Ten liners per pack means you've got enough for 10 full grow cycles — or 10 tubs running simultaneously if you're scaling up.
| Specification | Detail |
|---|---|
| Brand | Microppose |
| Quantity per pack | 10 liners |
| Available sizes | Small, Medium, Large |
| Material | Polyethylene film |
| Compatibility | Microppose Monotubs (size-matched) |
| Reusable | Single-use recommended for sterility |
| Sanitisation required | Yes — isopropyl alcohol before each use |
Complete your monotub setup with the Microppose Monotub itself — available in Small, Medium, and Large with built-in filter patches and moisture-resistant construction. If you're inoculating grain spawn, the Microppose Adherable Injection Ports (50-pack) make the process cleaner and faster. And for maintaining humidity between flushes, a fine-mist spray bottle is worth having on hand.
We get asked surprisingly often whether you can reuse these liners between grows. Technically, you could wash and re-sanitise one. But for the price of a single liner from a 10-pack, it's genuinely not worth the contamination risk. Mycelium residue clings to plastic at a microscopic level, and no amount of wiping guarantees sterility. Fresh liner, fresh grow, clean conscience. That's the whole point of buying them in packs of 10 — Microppose clearly designed these as a consumable, not a permanent fixture.
The other thing worth mentioning: these liners are specifically dimensioned for Microppose Monotubs. If you're using a different brand of monotub or a modified storage container, the fit won't be right. You'll get bunching, pooling, and the same problems you'd have with a cut-up bin bag. Stick to Microppose tubs with Microppose liners and everything lines up — literally.
Liners prevent side pinning by eliminating the gap between substrate and tub wall as the cake shrinks. They also keep the tub clean, so you skip the scrubbing between cycles and extend the life of your monotub.
They're cut to fit Microppose tubs specifically. In a different tub, the dimensions won't match — you'll get excess material bunching in corners, which defeats the purpose. For non-Microppose tubs, you'd need to cut your own liners to size.
Yes. Wipe both sides with 70% isopropyl alcohol right before placing it in your sanitised tub. The liner comes clean from the packaging, but "clean" and "sterile" aren't the same thing in mushroom cultivation.
One liner per grow cycle, so a single 10-pack covers 10 full cycles in one tub. If you're running multiple tubs simultaneously, divide accordingly — 5 tubs means 2 cycles per tub from one pack.
No. The liner is inert polyethylene — it doesn't interact with your substrate or mycelium. If anything, yields can improve slightly because energy that would go into side pins gets redirected to the top fruiting surface.
After your final flush, fold the excess liner over the top of the cake, lift the whole thing out, and bin it. The spent substrate is compostable if you separate it from the plastic. The liner itself goes in general waste.
Check the base of your tub — Microppose moulds the size into the plastic. If you can't find it, measure the internal base dimensions and compare against the Small, Medium, and Large Microppose Monotub specs on their product pages.
Last updated: April 2026
Medical disclaimer. This content is for informational purposes only and does not constitute medical advice. Consult a qualified healthcare provider before use of any substance.
