Well because when they're scared or nervy, boesemanis tend to fade in colour - especially females. My female boesemani was completely yellow in the store - not a hint of blue on her - and they didn't know what she was and sold me her as an australiam mutt for $1.59 or so. Of course in my mind I'm like "ha-ha!" Makes me feel so smart sometimes, when I can pun the sellers like that. Another one I got for cheap was a dwarf neon rainbow, who was completely unlabeled and the only fish of its kind in the store, so they sold me her for 99 cents as a random fish.
Aaaanyway - normally I see rainbows go for $12 or so, boesemanis, reds, turquoises, and such. Dwarf neons are usually $4-6. Celebes and threadfins I've seen for $3-4 or so actually. These are the prices I've spied at Petco. Most other LFS'es I know of hardly ever sell Rainbows.
Though personally I like the Australian two-dollar mutts, too. They are very inconsistent in type though, you see all sorts of different body shapes, fin types, colours and such. Well because they're not pure strains but rather generations of random rainbows bred in. The males can look very impressive though - especially the bigger ones - when they're in a good mood and show their colours.
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