Fungi infection: BRANCHIOMYCOSIS (GILL ROT)
How we spotted it
On Sunday 1st July we spotted this unfamiliar fungi infection known as Branchiomycosis or gill rot in our aquaponics system. The third one in our first greenhouse.
We figured it out merely because besides two Sarasa Goldfish we found dead one of our Koi carps.
As a matter of fact, I reported in the previous blog posts the high mortality rate of the Sarasa Goldfish we’ve just received. But we attributed the lack of blood in the gills to a nitrite poisoning. Diagnosis that made sense, especially considered the improper conditions of dispatch of these fish. Indeed, we weren’t completely wrong. That is to say that the trigger to the development of this fungi infection was actually the nitrite poisoning of the new entry. After all, we lost just the aforementioned Koi carp during the outbreak. (Unfortunately my father’s favorite one!) While the good health of the other Koi carps, Goldfish and Turkish crayfish – we have been raising for one year – prevented the infection to rapidly spread inside the tank.
In other words, it allowed us to identify it and take the steps necessary to eradicate it on time. And here comes the fun part. Since this specific fungi infection – that actually is a fungal infection – is commonly found in the Eastern European commercial fish production. It’s almost unknown in the rest of Europe. So, my father couldn’t detect it just seeking for it in any of his fish disease diagnostic books.
Therefore, with my usual stubbornness I looked for some answers on the net and I compared several fish illnesses with the same symptomatology. Then, I checked the suitable conditions for the disease onset and I saw if they matched with our aquaponics system’s. Like for instance the high levels of nutrients in the water (mainly due to the organic waste produced by crayfish). And also the water temperature above 20°C (68°F). Most noteworthy it was the geographical demarcation of the Branchiomycosis (gill rot). In fact, we bought this stock of fish from our usual dealer from Czech Republic.
Nevertheless, the first step consisted in isolating the Sarasa Goldfish from the other fish and crayfish. Then we treated them with an anti-fungal drug for fish. We changed the water of the aquaponics system and we treated it with a DIY solution as well for one week.
During this period we lost only other four Sarasa Goldfish and finally we were able to stop the epidemic.