ballastbelly
Contributor
i got one of these
scubastore.com/images/products/media/bestdivers_04348.jpg
it has 1 valve on top for air & other on bottom for water
but i can not figure out how to fill the bottom when at the sea side. no amount of holding the smb under water, inflated or not will get any water inside. am i supposed to use a syringe or something? thanks