Thanks for the suggestion DJT. I might have something in the future that would interest pondmeisters.
I'm considering a system inspired by two problems common to most ponds, lack of forage and overcrowding. Obviously the black soldier fly larvae are the additional forage, but the larvae would also be the motivation to harvest excess fish.
BSF grow very quickly when fed fish and most of us need to thin out our fish populations. Some of us eat fish, but there are still probably more culls than can be eaten. Instead of throwing them on the bank for the raccoons they would go right into a BioPod to be converted directly into additional forage. This way you aren't wasting any fish that you've raised. The feed and forage that went into making the culled fish goes back into the pond as high quality protein.
I've experimented with adding fresh fish to a BioPod and they don't create an odor issue. The larvae eat the fish so fast they don't get a chance to develop a bad smell. Of course there's a limit to how much a colony can process, but even if you add a little too much the smell shouldn't be horrible. If it did start to smell you would just stop adding fish for a few days and it would take care of itself. I usually make a few cuts in the fish to give the larvae an easy entrance into it.
I'm pretty sure that many pond owners would be motivated by a system like this. Feeding the larvae table scraps is cool, but feeding them fish that you raised and then feeding the larvae back to the remaining fish is even better. I think I've mentioned my idea of running a pipe from a BioPod out over a pond so that the larvae drop in automatically. With a set up like that the whole process would be as easy as dropping the fish into the unit and closing the lid. At the end of the year you could add the residue to your garden.
If you've followed this thread there isn't really anything new about this idea, but I think that if pond owners saw this cycle in action it would create some interest. A pound of larvae per day isn't a huge increase in forage, but you have to thin the herd anyway so why not recoup that protein? I want to gather some nutritional info about fish so that I can compare it to BSFL. The dry matter in BSFL is almost 50%, so a pound of larvae probably represents more than a pound of fish. This is the kind of information I'll be looking into.
