this is on Petcos website....
What is a Male Halfmoon Doubletail Plakat Betta?
Here is the details it lists for these guys
: S.E. Asia - Cambodia, Thailand
: Up to 3"
: 74° - 82°F
: KH 0-25, pH 6.0-8.0
: 1+ liter
: Betta splendens
I was noting they say they are community fish but they should be in at least a liter of water. yikes.