Haveagojoe
Fish Crazy
No no no the Edge is way to small for cardinals, I presume its the 23 ltr one, Ive got that and all thats in it is cherrys a couple of pink ramshorns and 6 lampeyes, you are very limited with that tank so watch your stocking, I,m not sure of the catfish don't know which one you mean but again corys are a no no cos they need air to breath and with the tiny aperture at the top of the tank it would be a real problem for them to get air, keep it simple stick with the shrimp for the time being and get a few cherrys youll soon have a breeding colony