I decided that I was sick of messing around with Fibre Fill on my grain jars for gas-exchange. Now, I know what you’re thinking ‘Garf, just use sterilised bags of grain’ and my answer to that is I don’t have a pressure cooker big enough for it to make sense just yet, I don’t want to run and setup my bubba barrel for a few bags of grain and I don’t really have the storage right now and I don’t have to make any more excuses!
On one of my outings I came across this absolute bargain of 12 jars for £2 with pre-drilled holes. The sceptic inside me said it was too good to be true but £2 is nothing so I thought I would give it a shot! I took home the last 2 crates and had some Lions Mane liquid culture ready to go ordered on eBay.


The reason I use hot water is because it expands the grain and causes it to release more of its dirt, it also does a fantastic job of speeding up the soaking process, by partially cooking the grain it softens the seed coat much quicker than regular soaking.
18 hours later I filled up 4 jars, stuffed the holes with Fibre fill, covered them in foil and popped them in the pressure cooker for 90 minutes @ 1 Bar (15psi). Low and behold they didn’t pop or break as I had anticipated they would.

A few days later I popped them in front of my HEPA and did the usual procedure being more careful since I didn’t have injection ports this time for reason I’ll explain further down the blog.
I cleaned the area and heated the needled up to glowing using a little handheld blowtorch lighter kind of thing used for cooking. Some people use lamps and some don’t bother since the needle and work area is, technically sterile, but I’ve never been one for doing things by halves!

I cracked the lids and injected 2.5ml of the Lion’s Mane LC into the first 1cm of the grain (usually you would go deeper but I didn’t want to risk contamination being pushed since it wasn’t a typical transfer)

Then popped them into my homemade incubator. Which is built from an old fridge off eBay, a reptile mat and a thermostat plug. It works an absolute treat but is quite small but incredibly well insulated. A chest freezer with some racking would work even better I think.

Now, earlier I said that I didn’t have an injection port. And from the pictures you can see I’ve just stuffed Fibre Fill, that’s because of a few things. Firstly, my injection ports are too small for the holes in the jar and consequently just fall straight through the hole, so I’ve ordered some new ones that are larger for the holes.

Secondly, I can’t get a decent cut for the new airflow design that I’m using, this is because the metal is so thin that drill bits just chew it, ideally, I would punch it out with a hole punch but because of the depth of the rim of the lid, it won’t fit in. My next step is to drill it smaller and ream it out, with any luck that will do. You can see below my practice.

So that’s my story. This is all for OCD to be honest, the only benefit from using a more tidy air exchange is less chance of contamination from ‘Wicking’ off the fibre fill, but if you’re careful you won’t get that anyway, you can get similar results from micropore tape and silicone. I chose this way because it looks neater, cheap jars and doesn’t require me to mess around with fibre fill or having to find the centre of the lid!
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You don’t need to take the lids off!
Just inject straight through the polyfil…
That’s a great point! Thanks for helping! Cheers!
Gareth