These fish like it a little on the warmer side. I've kept them from 25C upto 30C. They can grow large for a killifish so a 2foot tank would be great, but I've kept them in 1 foot square tanks all the way upto 4foot tanks. They will form a loose school and hang on the surface mainly.
They are very straight forward to look after and mine eat anything I feed them, from pellets to granules to flake and they never say no to live food. In summer I catch annoying flies in the house and put them in their tank and they love them!