Hi, this is my first time here so I hope I can get some real answers to this question. Today, I bought my FIRST BETTA FISH and I had bought maybe a gallon fish bowl for starters. The guy at PETCO told me when cleaning the bowl I don't even have to take the fish out of the bowl but take out maybe a 1/10 of the the dirty water and add a 1/10 of tap water with some Tap Water Solution that should be good for the fish ... meantime I'm hearing that I would have to take the fish out in a seperate bowl??? very confused ... don't wanna kill my first fish when I do this!! lol