crowded?
lol
it was a 12ft by 4ft by 3ft aquarium!
i could fit in it happily.... lol
filtration was running constantly, there were holes in the bottom of the tank via undergravel - gravity did most of it, and flow regulators (fancy way of saying taps lol) to ensure the water could be pumped back by the pumps at the rate that it was coming out by.
filter was home made-ish - massive carbon pod thing attached to a swimming pool pump and a whole load of media and sand and stuff - total pain to clean but only needed cleaning once in 6 months or so- water changes (about 25% from under the undergravel) once every month, and filter was drained once every two weeks... there was heaps of gravel by the time it was complete - about 2inches of polished amethist crystal... purple stuff looked awesome - haven't seen it in NZ though.
beef heart with the garlic thing is real good; i grated it and didn't blend it cause then it resembles bloodworms in the water, instead of crumbling to bits.... had a few bottom feeders - mainly cories....
tank held 300 discus in it at one stage - ranging from small $2 coin sized to full sized ones... sold them as they got bigger - its how i earned money as a kid, lol....