Backyard Aquaponics
A place to discuss aquaponics

Dear Backyeard aquaponics community



I have this weekend discover the death of 6 trout and it looks like the others are sick aswell so it could be the end of this first season making aquaponcs in the garden.


The sickness is like a paracite or fungus growing on the sides of the fishes and around it gills. it appears like a white fluff much like when one leaves bread in a bread bin too long.

There are cuts to the side of the fish.


It took me some time to see this as I have last month introduced iron chelate to my new system having discovered defitincies in my plants. The chelate I chose was the FEEDDHA which turned the water red. I did this after my research told me this was the best type for starting systems.

Anyhow when the fish started to die they floated to the surface and i could see some signs that sickness was a problem.

I got to thinking that maybe the trout need better visibility in the water and the feeddha is making it hard for them to see the food and therefore they are weakened and get sick.


This is a theory and I am putting it out there for those with more knowledge and experience to maybe shed some light.

A friend came by and said to me that it could be caused by not having enough moving water.
So i am at a loss as to what to do. I have installed a venturi pump to put lost of oxygen and i have been treating the tank with anti paracite stuff and hope to avoid total wipe out.


please let me know from my description what the sickness is?
Are there reasons to not use feeddha with trout?
and what i can do to stop Armageddon for my fish

The Chelated Iron will not harm the fish, not enough oxygen definitely will harm your fish, but not show any sign of sickness, they just die from lack of oxygen.

They'll swim near the surface gasping for air before dying, any sign of disease is not from lack of oxgen or Chelated Iron.

Without any photos it's hard to say what the problem is, you need to search Google for Trout parasite & fungus on the gills and try to match it.

Salting up may help if it is not too far advanced.

https://vfa.vic.gov.au/operational-poli ... water-fish
https://oac.cdlib.org/view?docId=kt5q2n ... brand=oac4
http://animalbiosciences.uoguelph.ca/aq ... 20Fish.pdf

What are your water test levels? Ph and Ammonia.

"Cuts on side of fish"

There must be something causing the cuts , I lost some catfish with cuts on their sides , I had a snipped off cable tie on my pump cable that was sharp .

A bit more info on your system will help , tank size , filtering system / size , fish numbers , pump flow rate .

How long have you had the fish in your system / how big are they

As above photos are a big help.

Short version trout need really "Polished Water" , naturally they live in fast flowing crystal clear water .

So if system is struggling to keep up , trouble will turn up .

Common causes of fish losses

High Ammonia followed by a Spike in Nitrite

Disease often introduced by us

Water temperature

Pump failure / power outages

Water leaks

Overstocked

The system is one ibc with one barrel halfed and made into beds. The beds are filled with hydrokorrels
there is a radial flow filter fitted and a sump tank
I estimate around 600ltr

There where 14 fish and now 6 are dead so i have 8 left
the water is crystal clear but the iron chelate and hiding places makes it difficult to see how many fish are really there and not dead. i could catch them but dont wont to stress them

The PH is 6.8
I dont have a ammonia test on the test kit i have and bought a seperate dropper one but recently ran out of it.
the NO3 Nitrate is between 50 and 100parts
and the Nitrite is 0

so from that I can see the bacteria in my beds is clearly working

I have worked out that my syphon was not triggering for a few days, thus the fish were baically swimming it dirt filled water

I quicky tried to do a water change.
I introduced a big venturi fitted pump and now there is alot of air in the water. visable from the foaming.


"Salting up may help if it is not too far advanced"
can you please help me to figure out what to do with salt, how much and a method

Salting up to 3ppt would be a good start, using Pool Salt, no iodized salt or any other additives.

Plain old pool salt, 1ppt is 1kg of salt per 1000L. If your FT is a 1000L, dissolve 1kg of salt in a bucket of your FT water then just poor it straight in the FT and give it a little mix. It will help the fish fight of nitrite poisoning.

3kgs of pool salt per 1000L of water will give you 3ppt.

Some of your plants may suffer, but it's better to lose plants than fish.