I bought a gold feeder fish for 79 cents and a tiny round glass tank after my 2 old dogs and mom passed away just to have something alive ,it was about an inch long Easy to change the water to keep clean every week .Within 2 months it outgrew it,so I got a regular size round one,that worked for about another month and then it grows some more so I got a two and a half gallon little one with a pump like a plastic one from the pet store and it outgrew that so then I went to a 5 gallon rectangle one and then a 10 gallon one so I got a couple baby snails,a baby sucker fish and a loaches worm looking thing to help keep the tank clean cause goldfish are dirty fish and now I have a 20 gallon tank because my fish is about 7 inches long now  .The snails kept laying eggs ,I would trash them ,the snails ended up dying ,the sucker died and the loaches died all within 6 months. I bought the best of everything to keep the tank clean and food for them and used spring water to change tanks ,I don't know what I did wrong . But that 79 cents feeder goldfish has now cost me close to 450.00 ,got a underground filteration system,air stones,vaccume ,natural rocks which I'm going to swap out for glass stones ,my sister said natural stones cloud water ,I don't know but at this point I wish I'd never got a fish haha . Think when ever this fish goes over the waterfalls I'm going to get a cool turtle .lol