隔离生病的金鱼。 检查水质。 清洁鱼缸并换水。 检查金鱼。

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
If you have a sick goldfish, it’s important to separate him from any other goldfish so that he doesn’t transmit any potential diseases. If you only have one goldfish, leave him in his tank.  If you move a sick goldfish to a “hospital” tank, transport him in plastic bag that is inside of a paper bag so that your goldfish doesn’t get stressed. You may want to fill the water in the new tank with water from the old tank, though if the water is causing your fish to die, this may exacerbate the proble