What fish to keep in the colder parts of NSW Australia?

Cunningstunter

I'm in Canberra - we see 6 degree water temps in winter and 25 degrees in summer.

I had SP going ok but couldn't heat the water and unfortunately I lost most of them recently (50 fish) /sigh

The (smaller) 50 trout have kept powering through the colder temps and I find there's about 2 months where it's too hot and we've eaten them all already.

Petesake

I'd be wrapping a single bed electric blanket around the tank with plenty of insulation over it and the rest of the tank and maybe even the GB's if they're exposed to the cold air. Get it wired up with a thermostat to around 16 degC, it might cost a bit to get it up to temp but once it's there the cost to change from 14 - 16 degC would be minimal. The thermo-current will keep the fishies happy.

Pete.

Gunagulla

Whether or not an electric blanket or 2 would be enough depends on what volume of water needs to be kept warm, and how exposed the GBs are to the cold night air.

For example, if we were talking about a total of 2000 litres of water that dropped 4 degrees overnight, then you'd need over 9kWh of energy to counteract that loss. A typical single bed electric blanket draws about 100W, and if you ran it for 24 hours per day, that's only 2.4kWh, so you'd need 8 of them in your system if you only ran them overnight (12 hours), with good thermal contact. It would also have to be very well insulated from the cold air so that you didnt't lose most of the heat to the environment.
Insulating the top of the GB from the cold night air would considerably reduce the amount of heat that would need to be added.

If you were paying 25c/kWh for your electricity, then it would cost 0.1*8*12*0.25 = $2.40/night to counteract a 4C drop in water temp.

Yavimaya

the singles i bought lately were even less, 50w each.

Petesake

The electric blanket(s) is a possible external fix although electricity is more expensive than natural gas. If you have gas hydronic house heating you may be able to tap into a heat exchanger and heat the actual water.

Pete.

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