mystery disease: body tremors, seizures, eventual death

[rjv23]

I breed paradise fish. I usually have a few thousand fish in various stages of development. over the past few months I have lost a couple adult breeder fish to a strange affliction. both had similar symptoms. but were separated by a few months. the fish were kept in a pond container in about 70L of water with other fish. the other fish seem not affected. generally the fish looks normal and healthy - no bloating or any outward skin symptoms. no rubbing or any real signs of stress. eats normally up until the symptoms start. the fish develops body tremors like uncontrolled spasms. between the spasms the fish hangs at the surface and has some labored breathing. I lost one a few days ago that that I had separated in a hospital tank. it was hanging at the surface and just not acting right. some panting and body tremors. I checked for velvet but no color loss, clamping or sheen on the body. I suspected flukes so gave it a potassium permanganate treatment bath which it seemed to handle without a problem  (I have a stock solution that I regularly treat my ponds with every month or so and the fish seem to handle it no problem). a few hours later, it spasmed and had a seizure, then sank to the bottom upside down like it died - frozen like a stone. when I came back a few hours later it was looking normal again but still occasionally hanging at the surface and breathing harder than usual. it was swimming fairly normal with some body shakes but still better than the spasmed sinking rock that it showed before. the next day it was dead on the surface. there was some salt I added to the hospital tank water to help it along, but nothing else. all my other fish are in several tubs but all in the same water. this fish expired in a day after I notice it hanging at the surface. the other fish in the tub are fine. the body tremors are pretty violent and its like the fish is hooked up to an electric prod. the other fish that have expired like this had similar tremors, even one in a breeding tank - yet the female with him was fine and had no symptoms. I am thinking it might be something genetic, but it is pretty rare considering the number of fish I keep and the age of the fish affected. if anyone has any suggestions it would be much appreciated.

[Colu]

Sound like something neurological with the symptoms your describing could be a genetic component what are your water parameters how old were the fish @rjv23

[rjv23]

On 7/11/2023 at 3:14 AM, Colu said:

Sound like something neurological with the symptoms your describing could be a genetic component what are your water parameters how old were the fish @rjv23

thank you for your reply.ph is between 6.8 and 7. EC is about 200. the water is filtered through a large carbon canister before the going into the ponds. I have raised fish in the same water for years and the symptoms did not start after a water change. the ponds were stable and without change for a week. temp is hot here lately, around 34d C, but this has also happened in cooler seasons. sorry, I dont test hardness, I have floating plants to handle amonia and nitrites with media canisters in the tanks for bacteria.. I would suspect ammonia if it werent for the body spasms.these are anabantoids si pretty hardy when it comes to DO and water parameters. fish were about 8~9 months old, just hitting maturity and breeding age. one died from this during the first setup with a female. disappointing because he was quite special, solid turquoise. sad to lose him before I got off spring.

Edited July 11, 2023 by rjv23

[nabokovfan87]

Is there farmland nearby that could contribute to pesticides in your water change?  Yes there is carbon canisters in the filtration, but potentially something leaked through or the canister is expired?

[rjv23]

hi, tks, yes thought of this and it is possible. there is some lead and other polutants in the water here. my systems run of muncipal treated water but that doesnt garanteed total safety.I use seachm conditioner during water canges and age water when possible.it is strange how it affects only odd fish, most are strong, healthy and vibrant. i may have to go to resin filters for heavy metals and dioxins. thank you for your reply.

[Colu]

On 7/11/2023 at 7:02 AM, rjv23 said:

hi, tks, yes thought of this and it is possible. there is some lead and other polutants in the water here. my systems run of muncipal treated water but that doesnt garanteed total safety.I use seachm conditioner during water canges and age water when possible.it is strange how it affects only odd fish, most are strong, healthy and vibrant. i may have to go to resin filters for heavy metals and dioxins. thank you for your reply.

heavy metal contamination can cause some of the symptoms your seeing but I would have expected it to have affected multiple fish not just two in separate ponds the fact your running carbon block filter and adding dechlorinator would lesson the effects of any potential contamination if something were to get thought in smaller quantities lead can build up over time in the body causing neurological disorders if your using seachems prime that removes lead and other heavy metals it's difficult to say for sure what the cause is at this point 

[rjv23]

again, tks for your reply.yes, it is a hard ailment to understand. it might be some kind of genetic quirk that shows up in a few fish. but I line and inteer cross my breeding program to try and prevent the lines from getting too concentrated. I posed here curious if some other breeders might have come across similar afflictions. anyway, 99%+ of my mish seem fine and not affected. it is disappointing when you lose one that is special. tks for your responses.