i have four angels in my tank a zebra striped a marbled and two pearl scaled ive had them for over a month now the two pearl scales are swimming very strangely the one is leaned up against the side of the tank at the surface and the other is completly on his side at the surface and both seem to be breathing fin and every once and a while the one swimming sideways will right himself and swim at the surface correctly for about a second. any ideas!!!? what it is how to help em.