suggested density of shade cloth liner in digester to avoid clogging with bacterial slime

[John Mitchell]

Hi Dean,

Approximately 4 years ago I experimented with a worm digester loosely following your suggestions.

I have experienced occasional drainage blockage of my tank.

I do not recall there being a suggestion to use shade cloth as a filter liner years ago.

Numerous options between 30% and 90% exist for the density of shade cloth.

Here is a link,         https://www.allaboutgardening.com/shade-cloth/

The higher the percentage of cloth, the tighter the knit or weave.

What % do you recommend to avoid clogging from bacterial slime?

[Dean Satchell]

Hi John,

Shadecloth has always been essential for lining the filter, both the floor and the walls. The floor and walls also require a cavity. There needs to be sufficient height to the walls above the filter media, so that if the influent volume exceeds the drainage through the media, the water filters through the shade cloth walls and doesn't carry solids with it. Some slime builds on the lower wall shadecloth, which is good because the water tends to drain through the media rather than the lower wall. The worms digest this slime so it doesn't build up, and it doesn't build up further up the wall. The key is to have sufficient wall height so that the vermifilter never overflows.

I've always just used ordinary windbreak cloth. You could use a normal sized shadecloth that isn't too coarse and isn't too fine. 

Cheers

Dean