Bactrus,
Nice find about Abate, didn't find much info with a quick search though what I did find looked promising. Didn't really give info if it is safe for plants and animals though.
Regarding waterboatman and backswimmers no I haven't gotten bit by them because I have not yet messed with them. Lucky for me I read that they do sometimes bite, and you have confirmed it. If they bite then at least they are fiesty enough to get at Mosquito larvaes. In fact next chance I get, I will try to feed them one or two and see if they do attack them. I do see daphnia/moina with them, so I'm not sure if they attach those or that they live with them until they become food for the waterboatmen.
Disadvantage with Aldrovanda is they are not active hunters as they are not mobile enough. The problem with waterboatmen is that they are just a stage, and eventually will get out of the water when they reach adulthood.
By the way, from what I understand waterboatmen don't bite, but backswimmers do. Backswimmers are most probably Notonecta glauca and is a good choice to control mosquito larvae, the smaller version water boatman eats algae and microorganism, so might not eat Mossie larvae. So if it bites you, then the species that you have is great against mossie larvaes
TTFN
Arvin