Hiya, in my experience they've been quite hardy little fish! They like very soft, very clean water, tannins, lots and lots of dense planting and really colour up with live food.
Re water quality: For context I'm in Manchester so have extremely soft dechlorinated tap water (less than 2dGh) with a pH of around 6. I also have emergent plants growth and dose very low fertilisers, so I'm not sure how they'd fair in a less filtered/ higher tech setup.
Mine eat frozen brine shrimp, ground-up bug bites and live food when I can get it (daphnea for ex). They are very movement motivated, so nothing that sinks too fast works well for them. They won't really pick off the bottom at all, and will sometimes eat from the surface, but it's not their preference.
They're pretty easy to sex although apparently difficult to breed in captivity - I believe they're egg scatterers, but it's not very well documented. Mine display a lot at the moment, especially after live food. However, even if they are breeding in my tank I'm 90% certain they'd eat all the fry anyway. They're voracious little hunters!
In my experience they are not the quiet, peaceful fish the online guides claim them to be. They are territorial, and will especially pick on each other when displaying and breeding (you'll notice the males have a dark red anal fin). I can imagine they would be quieter and more skittish if kept in a bare tank or with much larger fish, however they're quite confident with my green neons, chili rasboras and pygmy Corys. They will be territorial with everyone and anyone when breeding, and compete for food quite happily. They're also a very friendly little fish (they beg a lot), so I see quite a lot of them. They like having some open swimming space and usually shoal together there, but will retreat into the planting often.
This
article I found is quite good, so I recommend having a read! I've attached a picture of a male + a male displaying so you can get an idea. I hope you enjoy your lovely fish !
