I had the same experience as you did. Thanks for sharing. Please let me know where you order the ladybugs and the cost. I have the orange ladybugs, but not the bright red ones. The orange ones bite.

ALL Ladybugs bite, just that some are a bit more ornery.

Hmm, it is not the grown bugs that are known to eat a lot of aphids, but the black larvaes (or nymphes?) does. They look nothing like the red lady bugs. There is a super efficient wasp though, that layes eggs in the aphids, and withing in a few days they are all dead. Maybe you had a visit of a few of those?