I'm going to try organic raw agave nectar. Good source of calcium and shouldn't hurt the microbes.
Also molasses is a source of magnesium for your plants.
GB80
This is a better sugar than using BSM in your ACT/SST. I use organic BSM for teas but there are better options. This is one.
If you read up on how BSM is processed you probably wouldn't purchase it! This is not a earth friendly process!
I use it mainly out of habit but I've been eyeing up the agave goodn's lately at Whole Foods.