They vary from £2.45 to as much as £4.50 per, depending on size and where you buy them.
They are a small and rather pretty fish with great personality. They thrive in planted tanks but can be quite shy. They tend to hide a lot. Males can be territoraiaI and some people report conflicts between males resulting in injury although I have 2 males and only witnessed gentle sparring. I feed mine with hikari micro pellets and frozen mini bloodworm treats. Had 6 for around 10 months now, very hardy and suited to lower tropical range. (20-23c).
They tend to have sunken bellies when you buy them but should soon fill out with a good diet.
Great fish and perfect choice for nanos, the kind of fish you can watch for hours. I house my 6 with a couple of oto's in a 28l tank.