Not sure my female is actually a female.

[Ulyaoth]

Ok, about 2 months ago I bought a 'female' betta. 'She' was really small with a very subdued color(even after settling down and getting a bit more flushed out, was nearly colorless in the store but turned a light red) and short fins. But I was just watching and see she has pretty long fins, almost as long as the males I've had, and has grown really big, and is now a really deep red. Also, getting a bit aggressive against the platies, flaring at them constantly, do females even flare? I'll try to borrow a camera to get a picture. Not like it matters much, still got a great looking halfmoon for $2.50 then, just wondering, since I had a male in with her for a while and they got along fine until he started getting aggressive and nipped her fins a bit, took him out and he got ich and died .

[xxabc]

The picture is probably going to be the best thing. I wouldn't be surprised if 'she' was a 'he', but since you bought 'her' as a halfmoon, the chance lessens. I don't believe I've ever seen a male HM Plakat. And yes females can flair, and I've seen some with pretty long fins for a female. And what's the tank size? You shouldn't be keeping males/females together anyways, besides breeding.

And how much is a "while"? I would think the male would know if 'she' was actually a 'he' and fight immediately, but who knows.