Cryptocoryne species will melt with the introduction of Flourish Excel. Usually not at very low doses, but even just using it per the instructions will USUALLY harm the plant.
Blyxa japonica does fine with excel. Not sure about the subwassertang.
I've heard that Egeria densa doesn't react well to excel dosing, but i don't have any personal experience to back that claim up.
Not sure how Nymphaea spp. (specifically N. micrantha) would fare; i'd be interested in hearing myself. I bet it wouldn't do too well.
Blyxa japonica does fine with excel. Not sure about the subwassertang.
I've heard that Egeria densa doesn't react well to excel dosing, but i don't have any personal experience to back that claim up.
Not sure how Nymphaea spp. (specifically N. micrantha) would fare; i'd be interested in hearing myself. I bet it wouldn't do too well.