Tilapia

[bigdaddy]

Hi everyone,

I was just wondering if tilapia were not allowed to be grown in some states of Australia or more to the point, is it legal to grow them in South Australia?

Cheers

[GaryD]

Hi BigDaddy,

Short answer is NO........see here.

Gary

[bigdaddy]

Hi Gary,

Thanks for that,thought so,
but may of investigated them further if it was legal.

I've got my veges in and the system is still cycling
Nitries at 0.25 and ammonia at 0.25.
I have 20 Barra doing well, now 150 mm
At the moment they are growing at about 10mm per week I was wondering if they would be OK in my system as it is? or, could I add more fish and if so what type?Maybe some Jade or even Golden perch?I don't really know.Or just keep it as it is?

What would you do ?

p.s. I hope to attach some photos of my system soon.

Cheers

[GaryD]

Hi,

Your big challenge will be to keep your barramundi at a reasonable temperature as you move into the colder weather. I took barra through last winter but I live in Brisbane.....and it was still too cold for them so I had to run heaters in my tank and that just makes them too expensive.

I'd probably leave things as they are at the moment. Try and get as much size on your fish as possible.

If you can line up some trout fingerlings, you might be able to turn off a crop of trout......but you'll need more fish tanks.

Think about setting up a fingerling system so that you can start to rear fish consistent with the seasons. Ideally, your barra should be in the freezer before the temperatures drop too far.

I have a single jade perch in with my remaining barramundi but they are all larger fish......otherwise I'm sure that there would be a bit of mayhem.

Gary

[bigdaddy]

Hi,

Yes my thoughts exactly,

The temp gets down to 0-5C overnight.

The bloke in the pet shop recommended 1 300 watt Jaeger heater and said thats what and all he uses for his shop it was rated for 1000l.I don't really want to purchase another heater and will but would prefer not to build an weatherproof enclosure around the tanks.

The first night below 20C came along and like I thought, it did not cut the mustard I brought just 1 more and it worked OK I am not sure if it will be sufficient for winter alone.

I 'm open to any low cost ideas to stop the heat escaping e.g some one suggested bubble wrap and that seemed to help to the tune of 1C

Re Trout fingerlings

I originally thought I would try some rainbow trout but knew they would not survive our summer as it turned out the tank water go to 32C so I decided to go for Barra knowing it would be a challenge in he winter.

I have 3 X 220 l drums same as the left hand drums on my system if I joined them up together, how many trout fingerlings do you think I should get? .We do have a good trout farm not to far away from where we live and I reckon any time soon they will have some fingerlings ready.

Cheers.

[GaryD]

Hi BigDaddy,

I don't really want to purchase another heater and will but would prefer not to build an weatherproof enclosure around the tanks.

Is there some way you can cover the tanks? Most heat loss will occur at the point where the water contacts air.

Could you use something like the mini-greenhouses in the photos......they'll heat things up during the day and help to retain the heat overnight. They are light enough that you can just drop them over your tank.....or remove them.....as required.

The first night below 20C came along and like I thought, it did not cut the mustard I brought just 1 more and it worked OK I am not sure if it will be sufficient for winter alone.

You won't like the power bill that these heaters will generate.

I 'm open to any low cost ideas to stop the heat escaping e.g some one suggested bubble wrap and that seemed to help to the tune of 1C

It might be worth a try......but, in the same way that most heat loss occurs at the interface between air and water, that's the case with aeration. Aeration is not the product of blowing bubbles in the water.....but rather creating/moving the surface of the water so that it is exposed to air.....so, if you're going to cover the surface of the water with bubble wrap/pool blanket, make sure you've sufficient aeration happening under the blanket.

I originally thought I would try some rainbow trout but knew they would not survive our summer as it turned out the tank water go to 32C so I decided to go for Barra knowing it would be a challenge in he winter.

The ideal situation would be to grow the barramundi in the hot weather and trout in the cold weather.

Under this regime, you would obtain barramundi fingerlings before the onset of summer. Even if you got them when it was still too cold, they are so small that they can be kept in a small tank which can be cost effectively heated. You get them to a size where, once the warmer weather arrives, you can shovel the feed into them with the idea that they are ready for harvest by the end of summer.

You would obtain your trout fingerlings as early as possible (even if was a bit warm) and keep them in a small tank where you could cost effectively control the temperature. Once the temperatures begin to drop (and they begin to put on some size) you move them outside and shovel the feed into them.

I have yet to test this hypothesis. It's a matter of the dates lining up. I know you can get barramundi almost year round from West Beach Aquaculture.....and you can buy them at an advance size..... so they shouldn't be a problem. If you can reconcile the trout in such a regime it might be possible to grow the two species out.....each at the optimum temperature.

Others might have some ideas on this. When are trout fingerlings available?

I have 3 X 220 l drums same as the left hand drums on my system if I joined them up together, how many trout fingerlings do you think I should get? .We do have a good trout farm not to far away from where we live and I reckon any time soon they will have some fingerlings ready.

That depends on how you set them up (mechanical and biological filtration) and how well you can manage the water quality parameters (aeration, temperature, etc.).

Gary

[bigdaddy]

Hi Gary,

For those who are interested,

I've just phoned up Tooperang trout farm and got some info.
Open Sat, Sun and public holidays 10-5

Rainbow trout available now 4-41/2" 100-110mm Long.
Water temps. OK up to 22C.
26C is fatal.
Require air.
Feed with floating pellets.
Grow approx 1" per month depending on a few factors of course

I used W.B.A. to get my Barramundi.

I might join those barrels together put aeration in them and build another grow bed and put may be 30 Rainbow trout into the tanks??ASAP.

I would prefer just to have a media filled grow bed only, for the filter,if I could(similar to what I have now).

What do people think about that number of trout?

I think I will persevere with the Barra (at least until the next power bill),hopefully until Christmas.Then do what you suggested,grow trout in the winter and barra in the summer,and see how it goes.Which will mean getting some more(maybe another 20) Barramundi,September/October.

What do people think?

Cheers.