One pair in a small tank, or?

I am wondering too, – I have tried several different ways, – but mainly now also keep them in 12 liter tanks, one pair.
And with these I have to admit :blush: that the succesfull ones are the ‘old’ and sometimes not so perfectly clean tanks.
It seems to me that some pairs need a lot of time, with several attempts, and then I leave them to do that, and in time the tanks become full of javemoss and spagnum / leaves that are decomposing. But I also think that this actually is what makes it possible for any tiny fry to survive, even when I havent seen the eggs at all.
This happened with my parvulus, which I considered the most difficult species I have yet had, and I didnt really think they would succeed. But I had one pair that seemed very harmonious and they obviously had nests and eggs, because sometimes the male dissappeared for longer periods. The water in this tank is not even all that ‘low ph’ – just around 6.5. But I have now seen two small fishes, of clearly different ages, – so something is going well in there.
The same happened with a pair of linkei’s.
But I have also had successfull breedings in tanks with several fish, – small ‘flocks’ of maybe 6-8 fish, but of course with many caves and hiding spots.

BUT – this way you never get a big bunch of fryes, you get one and two, and maybe more, but not many. And for this reason I sometimes wonder if it would be worth while to try the more intensive breeding. I think if a pair is ‘ready’, it might succeed, but sometimes they just arent, and you end up waiting for months where nothing is happening.