[ian14]

No idea what "flake soil" is.
I use coir.

 

[ian14]

So Flake Soil is what beetle keepers and millipede owner use to raise larvae of the Flower/Stag/Rhino beetle. It's make from hardwood and fermented, however, I am unable to source the materials to be able to make it atm as i have never tried.. It's quite expensive to buy and was looking for some advance on what others use here in the UK... Most people in the US seem to have access to oak pellets or fine sawdust..

Oh I see.
I just checked The Spider Shop, they sell it. £9 for 3 litres.
A quick Google search brings up plenty of oak pellets for sale in the UK. The same was true for fine sawdust.