Backyard Aquaponics
A place to discuss aquaponics

Hi All,

Well I'm going away for 2 weeks very shortly and have organised someone (who is not an APer) to come and feed my Trout.

The Trout have survived on a day by day basis, I have 10 (of varying sizes) in about 750L, and for the most part they've been quite happy as it's been a cool start to summer in the Adelaide Hills. They are well 'aired' and I've shaded the tank as best I can, but the water is around 20C at the moment.

Forecast for the next week has temps climbing into the 30's, even though the night temps will be up to 19C, I fear the temps might get too hot over time and they could keel over, and I don't want the poor guy having to fish dead fish out of the tank.

Should I just bite the bullet and finish them off? I've got some urea that can be used to feed the tank while I'm gone (I was thinking of a teaspoon every 2nd or 3rd day) to keep the system going, and then get some Silvers when I return.

What would be the best course of action?

Thanks,

Dustin

Harvest the trout. If only 2 weeks I would just let the system run by itself.

Yep, system will be fine to run for a long time without adding anything if you take the fish out now..

Two things ring alarm bells for me here, the first is having someone feed fish while you are away, often they are better off not being fed than to have someone else feed them too much. I have heard this story a thousand times.
The second thing is trying to keep trout as the temps rise - I ask why?
Isn't the idea of growing eating fish, that you will harvest them while they are healthy and enjoy having/ eating/ freezing home grown produce.
The system will be fine without fish for two weeks, add seasol if you want. There is stuff going on in the beds that continues to work and act as a slow release nutrient, so harvest your fish and have a trouble free holiday, mission accomplished!
Imho!

I'm not overly concerned with over feeding, the cup I have provided won't over feed on a daily basis.

I got the Trout at the beginning of June, 3 of them are quite large, a couple mid size and a few smaller ones.

I was hoping to get some Barra, but the grow out time will be too short by the time the water cools down (and I don't want to heat the tank), which could be earlier than normal if it's a cool summer. Unless of course I can grow out Barra in 4 months, evening water temps have been high teens and don't want to kill the Barra over night.

So I was kind of trying to get Trout as big as possible before it is impractical to keep them (I don't want to cool the tank either )

The bigger Trout I was going to grill whole, while the littler ones I was going to smoke and turn into smoked Trout dip.

Thanks for the advice, I might just finish them off and let the system run.

Cull them

+1

Ditto to all the above, cull them. Trout are the only fish I am going to grow seasonally from now on, and will just have silvers, catfish and maybe cod that can survive all year. Less worry this way, but with seasonal fish you must bite the bullet and cull even if some are smaller than you would like.
Hey, you can smoke the small ones, and all is good, yeah

Cool. Culling it is, a nice ice bath and a skewer to the head

Would I just be better off with Silvers than trying to do the seasonal thing with Trout/Barra?

With one system its your call. Do you want to do trout/barra and be prepared to worry about temps at the end of each season, and most probably lose fish. Or, get silvers and catfish which live happily together, or maybe try murray cod but they eat each other and more worry there.

You might be able to get away with Barra... as you can probably get them now at 100-150mm size...

But you still might have to heat towards the end of summer if we have a cool summer...

Would your air and water temp stay up until Easter/Anzac day??...

hmm not sure about that Rupe, especially if it's a cool summer. While Autumn is usually pretty stable (sunny, mid 20's), the evening temps can get to the mid teens quite often. Mean Max and Min temps are 20C and 12C respectively for April where I am (up to '96).

I've been thinking of cheapish and effective ways of heating and cooling the water when necessary. Such as a coil of black poly on a separate pump circulating the FT water, not pumping at night, using a couple of 200L black pickle barrels as a heatsink and that sort of thing. I am also looking at getting a bigger FT (1000/1500/2000L) to better stabilise the temps.

Maybe Silvers or similar are a better long term solution for the Hills.

If in doubt, why not do the silvers for the next 18 months, get them to plate size and do trout again?

Well harvest them I did, here they are! 10 Rainbow Trout, the biggest weighed in at 390gms, the smallest at 130gms. 5 were over 200gms (4 over 250gms). The bigger ones are likely to be grilled, the little ones likely to be smoked.

Hope it's ok to feed the guts and heads to my chickens. Guess I'll find out

Happy to see
Are you pleased with the result?