Underweight: the head will be wider than the fishes body Overweight: the fishes body will have a disproportionally large pot belly (please note that certain kind of fancy goldfish such as ranchu, pearl scales and lionhead naturally have a pot belly)
You simply look at it and compare it to other fish that you have seen. Bloat is usually accompanied by the fish being unstable in the water. If the fishes scales are sticking out like a rasp/file the fish has Dropsy which is a terminal, uncureable disease usually caused by bad water conditions.
It's not that easy to tell the age of a goldfish after awhile. You may be able to get a general guess if you are the original owner and have an idea of when you bought the fish, but otherwise it's too difficult to say for sure.
To know how old your goldfish is, you would need to know when it was born. You can take it to a pet store and have them guess, but it may not be accurate.
A one human year old goldfish, is eighteen goldfish years old.
for only he goldfish or fish know that
If it is as old as a goldfish that can, it can.
Normally goldfish are peaceful and calm.But incase your goldfish is doing so then its better to separate the new goldfish.
43 years old
well it just depends how old it is
It depends. A feeder goldfish lives to be about 2 years old. A fancy goldfish, (Black Moors, Fantails, etc...) can live to twenty years or more with proper care.
20 years
He doesn't know how to.
I don't know except do not put goldfish in the same tank as anything else the other thing will die. I know from experience. :*(
no never put suckerfish with goldfish as they will suck the slimes and scales off the goldfish and kill them. as for shrimp, i dont know???
Goldfish spawn in groups in springtime when the water temperature approaches 70F. They do not have live babies.