I have the happiest corys as soon as I changed from gravel to sand they've just been happy as they rearrange my sand to there pleasure very cool especially when I see them shooting sand out there gills very happy w. The choice I've made
What I love is, after you've done a water change and clean up the sand is nice and smooth, then when you come down the next morning, all the sand is covered in dimples from their little noses