this week alone ive already lost two of my angels to disease which i cannot seem to treat and im starting to see symptoms in two of my other angels. i really want to nip this before it gets my adult marble and leopard angels!! symptoms include: darting suddenly, hanging around in the back corner of the tank with their face pointed up like their looking at the top of the tank, and then ill wake up the next morning to the fish laying on the bottom and floundering around like it has lost control of its body, floating upside down and sideways. ive already tried using erythromycin to no avail thinking this is a bacterial infection of the swim bladder. any help and insight is appreciated!!!!!