Preparing for the Hot and Wet

[kenc45]

I am hoping to set up my first Aquaponics garden soon. While many of you are battling through the cold down south, weather up here is mid 30's everyday, with nights around 10-15.

My fear is with the heat up here. Most days for a few months, Oct-Dec normally, are high 30's to low 40's with high humidity, then it stays really hot through till April, but there is occassional relief as there is lots of rain. I'm afraid that the water temp is going to get too hot for the fish. I'm thinking of getting Jade perch. What would be too warm, does anyone know?

I am also afraid that the grow beds might get too hot for the plants if they are in the sun, but at the same time, I'm worried about them not growing well if they are in the shade.

As a starting system, I'm thinking of getting one of Murray/GaryD's kits with 3 beds. This is because this is a rental, and I'm not always going to be in Kununurra - so I wanted to be able to move the system (if not the fish). For safety reasons, it'll need a cover (the neighbour's kids sometimes jump the fence for the footy), so I think that'll add to heat retention.

Has anyone advice to offer on ways to set it up to cope with the heat?

[Martin A1]

G'Day Mate,
Why not grow Barra? They like it hot I believe!
The rain could be a problem solved by some sort of shelter.

[kenc45]

Hi Martin,

One reason is that Barra are easily caught up here, and everyone tells me how much better that barra is to aquaculture barra. Still, that in itself wouldn't stop me if I thought that it was the right fish.

I am under the (perhaps mistaken) belief that they are carnivors. Is that right? Does that mean that they don't eat things like Duckweed, and silverbeet, etc. I really want a fish that works in well with the overall system. Do you know if Barra eat things like Roaches, or worms? I'll do some research on them.

[Hamish]

Some shade cloth to keep the mid day sun off your veges should work fine. Keep the tank in the shade too.

Growing some climbing veges like beans and tomatos over the grow beds with a simple frame would also shade the grow beds but you will probably still need shade cloth.

Jades are great with the highest omega 3 content of 200 species tested.

A quick Google search turned up this reading material on Jade Perch.

http://www2.dpi.qld.gov.au/fishweb/14076.html

http://www.ausyfish.com/jade_perch.htm

http://www.aquaculturequeensland.com/jade_perch.htm

[djs-sa]

the barra in my aquarium seem to eat any thing that all my tropicals eat and 1frozen type I give them has plant matter in it.
but my barra tanks are only fed high protein pellets(gro best and skretting for large pellets)
if u get lots of sizes they will eat their little mates, this seems to be a problem when the fingerlings are smaller than 100-120 mm,
by this stage u have sorted the bolters and runts and most fish are growing at the same rate be that stage
first 5-6weeks i spose

[kenc45]

Hamish, thanks for the info. I looked that the sites, and saved a copy of some of the info - then looked up Barra on the same site. I'll try something with shade cloth.

DJS, I have to say that fish that eat each other put me off a bit - because I think that I'll lose enough of them by myself without them helping out.

Martin, I forgot to ask: Why is rain a problem? I have read it a number of times? Is it because it can overflow the system, or upset the level?

[GaryD]

Hi Ken,


DJS, I have to say that fish that eat each other put me off a bit - because I think that I'll lose enough of them by myself without them helping out.
Most species of fish get into a bit of cannibalism. For some, like Murray cod, and Barramundi, it's completely natural......they just like to eat fish. For others (like Silver perch, it's opportunism......if something swims by and it will fit in the mouth, it's lunch.

Gary

[Hamish]

Hamish, thanks for the info. I looked that the sites, and saved a copy of some of the info - then looked up Barra on the same site. I'll try something with shade cloth.

DJS, I have to say that fish that eat each other put me off a bit - because I think that I'll lose enough of them by myself without them helping out.

Martin, I forgot to ask: Why is rain a problem? I have read it a number of times? Is it because it can overflow the system, or upset the level?
I think you will find the rain issue is more about upsetting levels. Overflowing a system is not a big deal as long as the overflow happens through a drain drilled in the side of the tank wih a mesh screen so the fish dont get sucked out. The up side is you get nice clean water - the down side is it may change pH and salinity - and you will be dumping the nitrates that you want in the system to feed the plants. Not to mention lowering bacteria numbers. My tank is outside but 2 of my grow beds are under cover. I have had to empty water out of my tank once when we had rain for a week solid. I have not got around to adding an overflow drain to my tank yet. The rain doesnt happen often these days!

[Outbackozzie]

I use selective pumping to control the temperatures in my system.

Winter - Day time pumping only, to gain heat. No shadecloth.

Summer - Night time pumping only, to reject heat. Lots of shadecloth.

I use waaaay oversized pumps so I can get a lot of water circulated during these time periods. My system is 5 degrees warmer in winter, and 10 degrees cooler in summer than a comparable system in my area.

[Hamish]

OBO - I have experienced the same thing. While I am heating my tank due to the small fingerlings I have I to am only turning the pump on between 7am and 7pm. I feel this is keeping the temp in the tank far warmer with less power used for heating. Before I started this timing cycle the temp in the tank would rapidly drop and the heater would stay on all night unable to keep up with the heat loss of the grow beds. Now the heater comes on at night infrequently. THe other big thing that helped my system retain heat was a foil backed closed cell foam insulation cover - really traps the heat into the tank.

[anniefish]

Hi all,
I have found I can't grow much without shade cloth, even here. The difference is very obvious. I also grow tall crops (corn, beans or gourds on trellis) on the western side of beds.

[Hamish]

I think my strawberries are suffering from too much direct sun and I might have to give them some shade. There is plenty of fruit but the leaves seem to dry out and die often.

[fishfood]

Hamish do you have salt in your system!

[Hamish]

Thats probably it FF. I am not going to add any more salt to my system unless have health issues with the fish. The weird thing is that there are lots of flowers and fruit on the strawberries.