Fishbowl with Mountains

Goldfish especially on the ammonia, they are little ammonia machines. Bettas aren't so bad, so they do ok with regular water changes. But as always, you should always try to give ANY fish you have the best environment you can, and filtration is always better than changing the water.

@Lisal - yup, Oscars are busy little aqua engineers (and they like to have their nose petted when someone walks by their tank).

The trick with keeping live plants is to have a rock infrastructure that makes getting to the base of the plant to small for the Oscars to get to (i.e. nooks and crannies made up of large heavy rocks).

Plus keep enough smaller rocks and "toys" in the tank so the Oscars have other things to keep themselves amused (like chasing live food).

Trying to imagine goldfish living in pongs. That would be very uncomfortable for the fish.

Vonskippy, you keep your oscars w/ live plants? I've always heard that they are very destructive fish b/c they like rearranging everything in their tank :P

WOO, I'm glad there are others out there who realize fish bowls should NOT be used for fish.
And no, not even bettas. ALL fish need a filtered environment IMO (well unless they're in a natural one of course heh). Ammonia can build up super quickly even if it is just a small fish and that= a dead fish.