whatis this filter/waterfall called and do they work well

[smkngstv]

this unit was purchased by me for my new indoor pond it has a good flow of water thur it about 2000 gph it is filled with a white pourus stone and is 15 x15 by 24 inches high,i added this as i think it will work well to degas the water but i am not sure if beniful bacteria will also grow in the rocks ,which will aid my filter system.

[ricshaw]

this unit was purchased by me for my new indoor pond it has a good flow of water thur it about 2000 gph it is filled with a white pourus stone and is 15 x15 by 24 inches high,i added this as i think it will work well to degas the water but i am not sure if beniful bacteria will also grow in the rocks ,which will aid my filter system.

A mini Japanese Lantern Zakki Shower?