fishes die

Hi. I have goldfish too and they are now 6 months old. The water of course should be clean. They should have plants or pump to give them enough oxygen. Don't feed them much. Feed them only once a day or maybe once in every two days. Give them little or just enough food. As what I have observe, they are always eating. The more food you give, the more they eat, the faster they die. LOL.

did you put the goldfish in the tank immediately as you add the water ? for what i know , its need to fill the water in the tank and switch on the pump to pump the water for at least 1 to 2 days before you can add in the fishes