The thing about swim diapers is they are not intended to be absorbent, if they were, then when your child entered the water the absorbent parts would soak up pool water and be completely saturated. Along with being uncomfortable and then useless as a diaper, this can also pose a safety hazard if the diaper becomes too heavy for your child and they might struggle to move in the water.
So the Bummis Swimmi is simply a mesh inner liner that catches waste (and yes, it will even catch the runny breastfed baby poo!), it does not absorb wetness. This might mean that when your baby is outside the pool you will need to put a different diaper on, or some people will lay a prefold inside their Bummis Swimmi to add some absorbency when baby is not in the water, just remove before they go back in.
|| 9 - 15 lbs / 4 - 7 kg
|| 15 - 22 lbs / 7 - 10 kg
|| 22 - 30 lbs / 10 - 13.5 kg
|| 30+ lbs / 7 - 10 kg