Backyard Aquaponics
A place to discuss aquaponics

Awesome info, thanks so much!

Just wondering, what's the lowest temps people have been able to successfully keep barramundi at? At what temperature will they begin to die off at? Mine are doing fine at the moment, just wondering whats the lowest setting I can have my thermostat at for them to survive.

Thanks in advance

-K98

Hi Kiara98
I wintered Barra last year in a insulated IBC with just a canister filter for filtration and had a single aquarium heater set on 20*, they did well. As I only had a small amount of filtration I kept the feed to a minimum. They feed better the warmer the water temp.

GTK

I just read an article where the author reckons he had them in his aquaponics system that got down to 14 degrees without any fatalities - seems very low for a warm water fish. He did state however that growth was very minimal, and that they ate minimal, became extremely docile etc.

I had mine down to 16-17 for a little while until I worked out a way to heat the water - they were fine, but did eat a lot less and growth obviously slowed right down.

Currently they are sitting at around 26 - will be interesting to see how warm the water will stay once we actually get some winter weather... It's now May and very little rain and only a handful of cold days/nights so far! Definitely increased in growth rates since I warmed the water!

Russ

Hi Kangaroodog
To fully understand why your fish are timid you will need to empathize with the fish so here goes

imagine you and all your friends exist in a comfortable glass cylinder suspended in a large pool, each of you in his/her own comfortable cylinder.
One day you awake to find the cylinder third from you is shattered and your friend is nowhere to be seen. you search around for your friend but alas no sign, but you do see some large fish actively feeding way below you.

HOW WOULD YOU FEEL?

Do your fish a favour.

If you have the fish in a glass tank .... provide a lot of cover.

If they are in an IBC then paint the outside black and put heavy shade cloth over the top.

Thanks friend

-K98

Interesting to know, thanks

-K98

Out of curiosity - does anyone know the effects of running at a lower PH then the recommended 7.5 to 8.5?
More prone to sickness? Slower growout?

I want to run them in a PH of 6.5, but I don't want to effect the growout speed and FCR ratios significantly if possible..

If you are going to sell these fish, you may want to ask them if they need larger fish. My biggest customer want's them around 5 lbs and is willing to pay bigger profit margins to get it. Also, I have yet to taste a difference in a 5 lb fish and a 1.5 lb barra unlike other fish. I can get a barra to 5 lbs within 27 months in my system but even a less advanced system could produce a 5 lb barra in 3 years. I know the wait is horrible but the paycheck is fantastic when I drop off 3,000 lbs of fish at $9 a pound for 5 lb fish vs. $4.50 at the 1.5 lb weight.