i am thinking about making my 15 gallon brackish. i currently have 5 mollies in it (2 yucatans, 1 sailfin, 1 dalmation, and 1 silver). What else could i put in it maybe a fan dancer goby and a dwarf puffer? If neccesary i can get rid of a couple of the mollies. i really would like a couple different kinds of small gobies and a couple of the mollies and maybe a dwarf puffer.