Will Falconer, DVM Moderator
I've not heard of this beer deterrent, but would suspect that it's a too simple approach. In my experience, heartworm prevention needs to address overall health and resistance to parasites of all kinds to be effective. That's what I outline in my HW ebook, Vital Animals Don't Get Heartworm.
I think you'll find the answers you seek there.
You've been doing well over the last year! Keep it up!