I would second the suggestion that Oscars are more interesting than pirahnas (my daughter adores her pair of Oscars a great deal - they will now eat from our hands and, like our dog, are always happy to see us).

My fishkeeping has been directed towards Discus. I have a very large tank which is populated by a number of large discus (mostly red turquoise and blue cobalt) a number of different tetras (black neons, rummy nose, etc) and some cory cats. The tank is quite beautiful.

As for filtration, I find that for messy fish, such as my daughter's Oscars, a combination of an internal filter (I think there's a Fluval 4 in there) in combination with an air-driven sponge filter provides good cleanup. Still, frequent vacuumings and water changes are required.

My discus tank is cleansed by a wet-dry filter system, backed up by a UV sterilizer and a canister filter which has diatom filter capability. I do vacuumings once every 2 weeks and change 25% of the water along with the cleanings.

Neither of the tanks has any odor. The Discus tank stands in my dining room. Always gets lots of comments from guests. Especially when I'm serving grilled Ahi or sushi.

Here's food for thought (pardon the pun). Spending time each day observing an aquarium has been discovered through research to have the effect of lowering blood pressure. I know it helps me after a particularly ridiculous day to go home and spend some time feeding and watching the fish and brushing my dog.

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David

His:
2003 Dodge Durango SLT
2002 BMW E39 530i Sport
1988 Mercedes 300TE
Hers:
2003 Chevrolet Suburban
1999 E430