Yes, that myth should have died out along with "sharp substrates ruin cory barbels." You can grow even the most delicate of plants in Flourite - glosso, even Elatine triandra... I wouldn't even consider hairgrass to be "delicate." I got mine as Eleocharis parvula, but I'm not 100% sure, because some of the blades on this thing reached a good 5" after it took off. And yes, it was 100% Flourite (less, if you consider all the MTS's that were crawling around in it. I had to get rid of all the hairgrass because this was a 2.5-gallon tank (8" high).