What is this filter called that seems to be in most store tanks that I've seen in videos? It's at 4:10 min in this video and many other times in most of the store tanks. It's a sponge that often seems to have plant matter growing from the sponge that the fish eat.
https://youtu.be/cJKQLnAaDlc
How come I've never seen a filter like that, which also has air bubbles coming from it being sold for home fish tanks? I was told I had to buy a filter and air pump separately.

That's a basic air-driven sponge. You buy the sponge and air pump separately. The plant and algae growth has just happened randomly; they are not meant to be planted. They are usually used in breeding tanks to save fry being sucked into a normal filter.
https://www.ebay.co.uk/itm/Air-Driven- ... YTQ&LH_ItemCondition=1000

OK thank you.
That was what I wanted to buy. I asked them in the store if I could buy a filter and air pump together, to save noise of two machines going, but they only gave me the option to buy separately.
I suppose so they could make more money.