Schistura spawning behaviour?

[Steve]

Hi, I've rarely posted in here but been lurking for a wee while now. I have a question about a change in behaviour in two of my schistura mahnerti which I've had for two years: in this time I've not noticed anything like it.

The past day, two of them - one is evidently female from the shape of her inc. a large belly - have been defending one area of the tank quite seriously (I use this word because they're a very playful fish, but this time there's more urgency to their activity). They've darkened considerably in colour, so they're nearly a solid deep gray, apart from the red dorsal fin, and they have occasionally been spiralling up the water column together, sort of half entwined.

I know nothing will come of this if it is, but does this sound like typical spawning behaviour for this species? Or, should I be worried about something...?

The only change in tank conditions is that I haven't changed the water this week since I've had a hectic time of it. They normally receive a 50% water change each week. The tank is 58G.

[Mad Duff]

I have 3 in my 250 gallon tank Steve and see exactly the same behaviour between the one male and two females, I wouldn't like to say for certain if it is spawning activity but its almost certainly nothing to be worried about