so i got a new betta and I have had him for a month or so. He seems to be happy and pretty calm tempered. When you hold a mirror up to him it takes him forever to puff up and sometimes he kind of swims away and hides from the mirror. I have had many other bettas before this one and I also had african dwarf frogs with every one of them and they seemed fine. Is it ok to put my betta with an african dwarf frog? what size of tank should I get?