Backyard Aquaponics
A place to discuss aquaponics

Hi Sarah,

the reason I got the Golden perch I did from Ausyfish was because the ones KE and I recieved from Aquablue were really really small, practically hatchlings..they were this way because of the travel involved. Before you buy them from anywhere ask how big they are and make sure they are weaned onto pellet food.
If you can get them at 40 to 50mm size (or bigger) and weaned, then get them.
As Rupe said they are slow growing so you need to get them nice and fat before winter so they can get through.

Himzo.

If you want locally produced golden perch you could try Andrew at 1aquaponics. He had some GP earlier in the year, and also has other species. He's out north near Lewiston/Two Wells somewhere, you could pick them up yourself and have them home in a couple of hours
http://www.1aquaponics.com.au/index.html
The problem getting fish from interstate is that if you buy 10-15mm fish they can put 100 in a bag for 3 days, but if you want 40-50mm fish they could probably only put 20-30 in a bag, therefore you'll have to pay extra freight per box.
It's pretty hard to go past trout though - fast grow out, exciting to watch, it's only a short drive to Mt Compass and you can get them for around $0.70. If you have them for 9-10 months of the year you can maintain your biofilter using urea or humonia for the other 2-3 months, or maybe just keep a couple of the smaller trout over summer with lots of O2 added.

Thanks Eric,

I contacted them now I have to choose between silvers (80mm) at $1.75 or 200mm Barramundi at $3. I know that there are a few people on the forum who live close to me (Hawthorndene and upper sturt) do you think Barra are viable here, maybe with some sort of polypipe solar heating?

only problem with poly pipe heating is you have a cloudy day and your temps drop. Generally using poly pipe, you are fighting a losing battle of up and down temps. Okay with electric backup and use the poly pipe on sunny days. If you get them at 200mm, you would be eating them within 5 months if you can keep the temp above 25.

Ooh a neighbour, I'm at Crafers West just of Waverly ridge road.

You could probably get away with the barra over the next five months if we don't have too many cool days in a row. I agree with Stu you need to have some other form of heating on standby in case we get a cool spell where overnight temps drop too low for the fish.
If you get the Silvers I think you'll find that they won't grow out to edible size until at least next season. Be prepaired to loose some over the winter. I had to move mine into a heated aquarium over last winter, still lost a few. Those that remain will be evicted to the outside this coming weekend and trout in that system culled.

Himzo.

yea, solar heating with pool heaters or a coil of black pipe does need to be controlled. As in only running the water to the heating panel or coil during the sunny part of the day.

I've been running a solar pool heater panel on the roof to a tank in an old ice chest. In there I have a coil of system water for heat exchanger so I'm not running system water through the pool heater (it would clog.) This way I can also run the solar heater during the day and then run the coil to the system at night to help keep temps up at night.
I've found this mildly effective this time of year but not so good during the coldest part of the year.

At what temp do Barras start to die? My water temp at the moment is sitting at 16. I've hooked op a 20m coil of poly thats in the sun sitting on a slab of slate. the output from this is about 1 degree warmer than tank and the flow rate will turn the tank over in about 4 hours. So I'm not expecting it to help all that much. What sort of heaters are suitable for an ibc? How expensive are the to run. How often am I likely to need it? I'm only thinking of running the barra through the summer then switching to trout.

think one kilowatt of heating per 1000 litres of water, possibly more if un-insulated. Barra will die at the temps you have there. They go off the feed below 20 and like any fish out of their comfort zone, are more susceptible to diseases etc

I got the tank up to 20 degrees today. Will be interesting to see what it goes down to over night. Monya I take you point about the dangers of having a marginal system... likely just to lead to problems and disapointment. I guess thats what I'm trying to gage, how marginal is it and for how long. I don't mind heating over night for the odd cold night as the weather warms up if I can then get a good growing season and be able to harvest before it gets cold. I found a very old CSIRO report (1958) that estimated the min temp for Barra at 15.5. I'm not that far off that which leads me to think that a bit of heating may get me through as I think thinks are going to be heating up here pretty soon.

How easy is it to get 1KW heaters?.....off to search

Thanks for the help everyone. I thinks its great how supportive everyone is.

BTW what fish to you have himzol? I'm just down the hill from Blackwood hopital

1KW heaters cost about $4.50 a day to run

Aquasonic would supply them ... http://www.aquasonic.com.au/brochures/h ... ochure.pdf

Or these guys... http://www.avk.com.au/chilling-heating/ ... d_141.html

But they're not cheap to buy... and not cheap to run...

going on what sarah has can you do trout in winter and barra/perch in summer. we live in the barossa and from my understanding the temperature is a lot more balanced if the fish tanks are in the ground?

Outside air temp at 6.50am was 15, tank temp was 16.5. I need to go and research insulating the ibc now. I found a couple of 500W heaters on ebay from hong kong but they might take a couple of weeks to arrive. My plants are already looking a bit hungry with nitrates at zero.



Thats why I said heating the odd night. Certainly wouldn't want to do lots of it.



I've had perch and trout together happily before.

Beware of cheap aquarium heaters from Hong Kong... or anywhere else for that matter...

The thermostats are usually garbage and don't work effectively, or at all... the heaters tehmselves often break easily (physically)... and many aren't probably rated to their "stated" capacities...

Most are NOT designed for FULL IMMERSION...

I really think barra are unsustainable. People in the adelaide hills should be doing trout for 9 months of the year and using goldfish or urea to keep the systems going thru summer.