identifying pure Endler's

Posted by Joseph on 2010/9/18 21:48:10

I'm thinking of setting aside some tank space for some Endler's livebearers, but have read that many aquarium populations are a mixture with common guppies.
Is this true? And if so, are there any markers that easily identify a mixed or pure population (I'd prefer to not waste space on an endler-like guppy hybrid)

Thanks.

Joseph.