I’m not sure you understood my point. I didn’t say it’s not feasible to work with a storage bin; in fact it’s the most common container used by myself and others. The only issue with them is that making a ramp system with rigid pipe takes a higher level of expertise than my bucket design. I’ve made very effective units with rectangular storage bins and someday when I refine the design a bit more and I’ll publish directions to build one.

Thanks for positive feedback.

Myself and others have worked with rectangular storage bins and pvc pipe ramps some of which can be found online. It can work, but in practice I think it’s more challenging to build than the bucket composter. The adjustments needed with the bucket ramp system are minor and only necessary once or twice a week usually. A sketch is a good starting point but the behavior of the larvae often causes unforeseen issues. The only reliable way to know if a design has merit is to test it with a colony. I look forward to more people working on DIY designs and I hope you have success with yours.

A potato sack might work; I would probably try several layers and also loosely stitching them together.

I read an Australian study that discovered that soldier grubs can break down meats faster then any regular composting bin if the % meat in the waste remains below 5%. The moment you add more than 5% per day of meats the meats seem to break down more slowly. At 10% meat per day there seems to be no difference between the grubs and the regular compost bin.

However, those are daily percentages. If you add 10% one day and add no meat the next you should be fine. Therefore your notion of 20% seems logical, as it would take 4 days to brake down. Anything mor than 4 days can start supporting blow flies.

I wouldn’t put any meets during bating.

Please be careful about feeding a lot of meat to your colony. It’s never a good idea to have meat sitting around rotting for days so if it isn’t being consumed by the larvae in about one day then I would cut back on the amount until new additions of it are gone within 24 hours. Spoiling meat is a good medium for growing botulism. This could be an issue for any animal that might eat the larvae raised on meat that developed this toxin. Processing meat is fine, but don’t overdo it; I would limit the percentage of meat to vegetable matter to about 20% just to be cautious.

“There’s still some solid stuff in there that’s old.”

I’m not sure what that means, but I would dispose of any animal product that remains uneaten after 24 hours.

“Should it be totally liquid before I add more food.”

I don’t think a BSF unit should ever contain waste that is totally liquid. Your BSF unit should have a drainage system that allows liquids to pass through quickly leaving the waste pile damp but not wet. A flooded BSF colony can become anaerobic which, if not corrected can lead to a crash of the system.

Based on your comments I can’t imagine that your colony is healthy or balanced, and I don’t expect it to remain functional for long. I recommend that you; remove and dispose of any uneaten meat, reduce the quantity of meat that you process to 20% of the total waste, add shredded office paper, sawdust, or wood shavings to absorb excess liquids. Please keep in mind that any bad odors are sign that your system needs attention.