I have successfully had a Betta 3 gal for a year, and have kept a tetra GloFish a friend gave me as a gift for a month or so now. I used to have some Buenos Aires Tetras but fluffy, the GloFish bullied them to death. I am nowhere near experienced in fish keeping so I blame myself. My 6.7 gallon tank is now practically empty. I would like to start a shrimp tank, but I’m not sure what I need. Once again I know my 6 gal is too small for a tetra, but it was gift. I also want to start fresh in fish keeping. So help me out, please.