In HK there's a place with least two block of streets full with lfs, all kinds of fish. many have fish in plastic bags just like in that video. I think they swap bags through out the day if air is running low and put them back into tanks when they close. usually only small fish is in the bag. everything is dirt cheap compare to here. I still remember I bought a baby black aro and african aro for ~$20 each but that was long time ago.