Backyard Aquaponics
A place to discuss aquaponics

Hi guys, I'm back.
My system has been very productive ever since I started it in 2013.
A year ago we moved house and eventually I managed to re-locate the old system to the new place.
A quick reminder - 1 ibc as the fish tank, solids lifting overflow to a radial flow filter, 8x half blue barrels, 1x 1/3 ibc as grow beds, sumps under all grow beds linked, flood and drain beds, red scoria media.
The system is very stable- 0 ammonia, 0 nitrites, Ph 7.3, 25ppm nitrates, 0 kh reading.
The Jade perch fingerlings went in on the 3 feb 2023, I lost 3 the first day, the bag they came in looked very dirty water with the fish not very active, the other three bags were clear and lively fish.
They are very active and have more than doubled in size but I am losing fish at a rate of 1-2 every 4 days.
The dead fish look no different from the live ones in form, I sliced them open and their guts appear to be full and a pale reddish colour but as I never did that before I have nothing to compare them with.
I feed them twice a day with pellets and they are voracious feeders.
In the last 9 years I only ever lost one fish that was dead on arrival.
I'm stumped, anyone any ideas?

Just a thought, could I be over feeding them?
How long can they go without food?

This one was swimming very listlessly at the edge of the tank about half way down this morning whilst the rest of the fish were going ballistic over the food.


5 hours later it was dead. heres its guts, I've never seen red spots before in their guts but then again I've never had dead fish before.

Sorry to hear you're losing fish. Not sure what's going on but either disease or transport issues (nitrite or ammonia levels got too high). I think based on your description that they were exposed to high nitrite levels during transport. Look at the gill color and that might tell you something. Slow die offs like this are typical when they have nitrite poisoning.

In cold water I feed my catfish once a week and tilapia 2x per week. I think they can go several days without food, no problems.

Definitely do not feed if ammonia and or nitrite are high.

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800 gal sys 2016
IBC sand-ponics system 2021, 3 IBC GBs

9 kW Solar Electric 2011 - Upgraded to 12 kW 2019

"Aquaponics...solar-powered nanotechnology that produces fresh vegetables and meat, while purifying water..." - Rick Op, Houston Texas.

I'm thinking that as well, that one bag of 25 was very cloudy and dirty looking and was semi deflated.
At least the water parameters are spot on.

Hi mate, how old is your water test kit?

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Skeg In The Hills.

4 months old
,
That fish was number 16 and so far the last one.
I'm convinced it was a bad bag full.
I dont think I will use that company again.
The remainder are growing fast and eating like mad.
Just how I remember the first fish 9 years ago.

Hi Savarin

I have had the same problem with my silver perch this year, first bag arrived with very little water and 20 fish in it. some dead and some not very well. very high ammonia and nitrite readings from the bag water. the fish were replaced but even with the new batch i got, still have had this slow die off all summer. 4 left and they also dont feed very well. new supplier for the next lot for me too.
it might be worth the trip to the fish farm about 90 mins away to get the next lot. i am in NSW.

hope you don't lose anymore

Mal

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Mal

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