I have managed to kill mint three separate times (well, once was "failure to propagate" which I was assured was not the same thing), so I'm definitely not one to give any advice. I could not manage to do the aquaponics thing, either. I was recently given a pot of live mint, which is doing okay so far. (I keep trying because it is supposed to be easy to grow, in fact difficult to kill, and my rabbits have expressed a preference for it.) Let me know if you would like a few plantlets, as it needs to be repotted soon. I also have around 1/4 cup of alfalfa seeds if you would like to try some as a cover crop.
If you would like any rabbit droppings to work into the soil to enrich it for the coming season, please let me know! I will be happy to bring you as much as you would like. They are parasite free (I checked them myself recently, plus rabbits don't really carry much of anything that can be transmitted to humans) and the poops don't smell unless they get wet.