Hypo is when you gradually(over a 48 hour period) take down the salinity of the water to about 1.009 to fight ick.
Refer to FAQ under Desease and treatment section of this board for info. on Q tanks. It's excellently authored by Beth. Good luck.
Do research on hypo before doing it though. Make sure you have the proper equipment (refractometer or digital hydrometer); something very accurate to measure s.g.
