wow you have a 20g with a tang and a mordian? wow. when people ask dont tell them your tank is thanks to AA. i hope you dont have any other pets that you would treat like that.
seriously this kinda pisses me off. excuse my rant but would you keep a saint bernard and make it like in a closet or a small cage? would you keep a throubreed and keep it in a 20foot dirt field and expect it to live. of course not because if you did you would go to jail or atleast be fined for inhuman treatment of animals. yet you can take 2 fish that have 0 business being in that tank and no one will do anything cause its fish.
its not a mandarin by the way, its a target goby