1) can it live with my Betta
2) do they need to be in a group
3) can one Cory catfish live in a 20 gal long? Here is my tank here https://www.amazon.com/dp/B0002AS21W/?tag=ff0d01-20
2) do they need to be in a group
3) can one Cory catfish live in a 20 gal long? Here is my tank here https://www.amazon.com/dp/B0002AS21W/?tag=ff0d01-20