So i guess i was right, so about the fries I got, what should I add in a tank? Substrate, filter?it looks like the yellow form of the blue panchax (Aplocheilus panchax).
What is the tank size for them?Rearing tanks for baby fish should contain a thin layer of sand or gravel substrate, an air operated sponge filter, and a heater if required (not an issue for you).
You can have some plants in the tank if you like and then just feed them and do regular water changes.