Backyard Aquaponics
A place to discuss aquaponics

Hello everyone.

The topic pretty much says it all - How big would barramundi and silver perch grow in IBC tanks?

I have had mine for about a year or so, with no deaths so far (surprisingly due to all the pH issues I had in the early stages of setting up the system and the lack of plant survivability )

One IBC has 4 barra in it (was 5, but I ate one a month or so ago at 32cm...) and the other has 10 silver perch.

The perch seem to be growing still (one big sucker, the rest considerably smaller) ranging from ~10cm up to ~35 cm whilst all the barra are around the same size (~30-35cm)

The barra have seemed to stop growing over the last couple of months and I'm beginning to wonder if their tank size is limiting them from growing? They still eat a heap, and the water is heated sitting around the 24 degree mark but they don't seem to get any bigger - definitely not growing any where near as fast as they used to!!

Basically what I am asking, do these varieties grow to the size of their tank or will they continue to grow as long as they have sufficient food?

Thanks in advance!

>> Basically what I am asking, do these varieties grow to the size of their tank

That agrees with my opinion but I am not sure where the science sits.
With goldfish I have seen some that spent years in a tank and stayed quite small suddenly grow when put into a pond.

Personally I feel there are limitations with growing fish to a moderate-large size in an IBC.
Circular aquaculture tanks that are 1000litres for example are actually much bigger tanks as they are 600mm high and have a larger surface area. Most AQ tanks would be 1500-2000 Litres plus.

Are you located in Perth or elsewhere ? Heating must have cost a bit - what did you use ?

The other possibility is that despite being heated the barra have had a seasonal response over winter.

Silver Perch would be less affected since they live in cooler areas, mostly they only slow due to cold so you have offset that.

Hello once again

yeah I am in Perth, and I'd like to not think what it cost to heat the water lol!! I'd suggest far more than what the fish would be worth in monetary value!

Its actually being heated through the spa - using the heat from the spa to heat the water... just ran some of the water through half a roll of poly floating around in the spa - works quite effectively, but will revise it next year if I bother to do it again. I'll separate the rest of the system and isolate a grow bed and the tank the barra are in instead of trying to heat the whole lot - Now have 10 odd dutch buckets, 2 x 1000ltr IBC fish tanks, 2 x half barrel grow beds and 1 x IBC grow bed and all the associated pipework... so a fair bit of area for heat loss!!

With a bit of chopping and changing of pipework, I'd probably just separate one fish tank and the IBC grow bed and insulate it all to minimise heat loss and maybe install a little 'greenhouse' type thing over it... I'd say it would cut the costs down massively If I was really keen, I could install a timer on the spa heater to only turn on during the day so the solar panels offset the electricity a bit too... Did it for a bit of a laugh to see how big they would grow, but I suspect I have reached their maximum size for the tank they're in so not much point really... will let them go over summer and see what happens as I will turn off the heating shortly when it warms up

Cheers
Rusty

Sounds like a solid setup Rusty!

How does the spa go

-K98

What size silver perch and barramundi are compatable with each other in the same tank?
Like, if I have a 10cm barramundi, what size does a silver perch have to be to avoid being eaten by the barramundi?

-K98