Thanks JHAP, I'm going to try and record them spawning.

I just got back from the pond and I offered several black soldier fly larvae to the bedding RES. I believe they don't eat much when they're guarding a bed but what the heck. One fish that is an adult stocked this spring ate one larvae. I imagine this could have been a protective behavior, but it took the food the way I've seen fish normally feeding. This particular RES isn't on a bed continuously at this point so maybe it's still actively feeding. Next time I try this I'll have my camera.

I was using the final stage coffee colored larvae today and I don't think they are as attractive to fish as the grub colored stages. I hope that fish will get acclimated to dark BSFL because they are the cleanest to handle and they're self harvesting.