(Virtual Scratch n’ Sniff v6.2)
It’s more accurate to say that a black soldier fly composter has a subtle, earthy aroma, plus the smell of whatever waste you’re processing. Some people compare the basic odor of a BSF colony to wet straw, but the main point is that it is not an offensive odor. If you’re smelling something foul in your BSF composter it’s not the larvae or their castings, it’s something else such as anaerobic bacteria and you need to change how you’re managing the system.
If you added the food shown above to a properly functioning BSF composter it would smell like those foods more than anything else. I realize you won’t be processing fresh food like that pictured above, but the point is that if you did then the aroma would be very similar to the fresh product. For example, once I added an entire loaf of stale cinnamon bread to my 5 gallon DIY bucket composter which I keep by the back door of our house. I walked by the composter a few hours after adding the bread and I was surprised by the delicious aroma of cinnamon. It’s not that the odor was just tolerable, it was appealing. Most of the time you probably won’t be adding something as aromatic as cinnamon in large quantities, so for the most part you shouldn’t notice anything but the subtle odors of the food scraps you’re processing. If you add bad smelling waste to your BSF unit it will smell similarly bad until the waste has been consumed.
Chronic bad odors can occur in a BSF unit, but it is a sign of imbalance which can usually be remedied fairly quickly. I know that some people reading this will be skeptical, especially those who have tried working with BSF with limited success, but I assure you I’m not exaggerating. I’ll be working on this post more in the near future and I will list several references to back up my assertions. I will also cover the causes of bad odors in detail as well as the remedies. For now I’ll add a quick quote from Kelly Slocum, a lady who has worked extensively with earthworms and also has considerable experience with black soldier fly larvae:
“I’ve worked on a few BSF waste processing systems, two of which were designed so that raw waste (usually hog manure) was processed initially by the BSF larvae, the poop from which (pretty liquid-y stuff) was stabilized by earthworms. These are remarkably efficient systems that process massive volumes of material each day and render the smelliest waste materials essentially odorless in just a few hours. I cannot emphasize enough the benefit of these flies or their suitability for working in conjunction with earthworms!” – Kelly S (SOURCE)
If you have experience working with BSF and can confirm my claim that foul odors are not a necessary aspect of it I hope you will post a comment below describing your experience.