tiger barbs mating?

[sourcy]

20 gallon tank, 3 tiger albino tiger barbs.
Just got these fish the other day.
Tank has been established sometime in february - over 1 month ago. Had a couple guppies, all of them died - probably because tank was not cycled..., but I kept the tank up and running, putting food in it to cycle, temp all the way up.
Added some tiger barbs the other day, I noticed one is a female and two are males (dark noses on the male, round belly on the other i susspect is a female, plus no dark nose on it)

Today all of the tiger barbs are sitting in the corner of the tank hidden under a bunch of fake plans. Then one of the males goes to the other side.

Is it possible they are mating already?
Water parms should be fine - 0 ammonia though the pH is high at 8.

EDIT: Or what could be going on? They were fine for the first two or three days I had them, and now they acting weird like that. However, it seems that one of the males and females stay together for the most part and the other male just hides in the corner. As of right now that's what happening.

[GBHammbone]

Males will have orange nose where females will usually be a cream/light orange color, but can be harder to tell in albinos. When mine are tryin to breed the males will get intense coloring on the nose and fins and chase the females almost non-stop. I have normal, green and albinos in my tank, and although they will school together the albinos seem to like hanging out separately even from each other, where the normals and greens usually stay in a school together most of the time. Also when breeding my females will get noticeably thicker in the belly when gravid. If yours do breed, they will eat their eggs. Hope this helps even a little bit.