- One small Betta Keeper® makes a wonderful desktop or counter top display piece or create spectacular eye-catching displays by stacking several units. - Ridges on the lids allow for stacking multiple small Betta Keepers® or to mix with large Betta Keeper® units. - When in close proximity with one another, Bettas are stimulated to intensify their colors, spread their fins and flare their gills. - Liquid volume - 24oz