My friend has a small Rukin goldfish. She has it in a 10g with little agitation and poor filtration. After, asking non-stop if I could have the goldfish she finally decided to "Think about it". Currently, I have two small Orandas in a 29g with a canister filter that does 350ghp I do 70% - 80% water changes every 5 days. I know I can support another small fancy goldfish but I'm not sure if I can support three when they become adults. So, should I take on my friends Rukin or leave it to suffer in a 10g? My main concern is that three fancies will be too much on the tank and filter. Please help!