Bettas, Gouramis, Rasboras, oh my!

No need to get so offended. Different people have different methods for achieving a good community in their aquariums. Mine is just one of many and it's never given me any trouble.

Like I said, it works well with peaceful community fishes. I never said to just go running blindly into petshops and buying oscars and guppies and goldfish and throwing them together. Any kind of aquarium purchase should be done with a measure of common sense. When unsure about a certain type of fish, research it before purchase. But as a general guideline for the more common aquarium species seen in most petshops, the one inch rule has never failed me and I would suggest it to anyone buying fish for a beginner's aquarium.
 
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