You know, this isnt advice but I felt I should put it somewhere.
I was at work [store] and I saw a guy looking at filters so I offered some assistance. Turns out he has a 10g tank with 4 big goldfish. I tried to get him to upgrade his tank size but he wouldnt because it wouldnt fit on his nightstand. This guy was around 50 something and wearing a work suit. He was looking at purchasing a new filter because his tank was dirty. He said he doesnt do water changes because his filter does all the work. I explained everything to him but he still refused. He wanted to get an ac
50 and I told him he shouldnt. I ended up selling him an ac110 for 35 $ because the box was cut open. The ac
110 is for a 10g tank! I hope it makes the fish a bit happier while they strive to survive in there