Nope goldfish are coldwater, I can remember years ago, when i was a kid, in
the UK, many,many years ago . My old man had a fish pond, and many a
winter the pond was frozen , and the fish where trapped in the ice, My old
man would crack the ice with a hammer, and the fish would get out and go
deeper in the water.
I,m in Oz now, and also have friends with goldfish, they also don't bother
with heaters.
bassett


Lucky" wrote in message
It's approaching winter in Australia and I have noticed the temperature
in my fish tank has dropped as the weather is getting colder. In the
warmer months the temperature ranged from 25C (77F) to 27C (81F) and
the fish didn't have a problem with this fluctuation. Now the water
temperature is about 21C (70F).

Before buying a heater I decided to read up on the net about whether or
not this is necessary and there are many varying opinions:

Some say the temp should be kept steady or the fih will be shocked.
Some say the temp can fluctuate from warm to nearly freezing and the
fish can easily cope with this.
Most say a heater is not necessary.

So I would like your opinions- please tell me what is successful for
your fish and also if you have any knowledge about why/why not a heater
should be used?

Thanks for your help!

Alex.

P.S. The tank is kept in an area where there is sunlight however it is
NOT direct sunlight. It just so happens that the house gets a bit cold
in the winter time. So the position of the tank isn't the problem here.