Just going by your video.But it looks like some cyano growing on the sponge to your maxi-jet.And you've got some algae and what looks like diatoms popping up.Thats whats causing the bubbles.
Take the sponges and soak them in a bleach solution.Just be sure to rinse them several times in fresh water,then soak them in water and chlorine remover for a couple of hours before putting them back on.
Run some phosphate removing media,either phos-ban or rowa-phos.
What are your nitrate levels?