Wicked mystery infection on African Cichlids

Hey guys
I’ve been dealing with a nasty, unrelenting sickness in my Cichlid tank. Before I get into details, I’m going to answer the basic questions first. No, I hadn’t added any new fish to my tank. The last time I did, it was about two months prior. My Ph is a 7.6; I have a mixed cichlid tank so I keep my Ph in the middle ground. All of my fish have been kept at this consistent Ph since I first started in the hobby nine months ago. My ammonia is 0.0ppm, nitrates are at 20ppm, and nitrite is 0.0ppm. I do 30% water changes every two weeks and rinse/change my filter media as needed.
This issues arose legitimately over night. I did my normal water change, and within a day (maybe two days tops), I noticed one of my fish had really milky eyes with a pimple like growth directly on top of his pupil. I noticed a film starting to develop over the eyes on a couple of my other fish too. There were no other signs of disease and I opted to treat the tank. Initially, I thought it was just a really bad case of cloud eye or a possible fungus. I medicated with melafix, primafix, and aquarium salt. Another few days went by and it only got worse.
I thought I had diagnosed them wrong so I switched gears. Thinking it may be a parasite of some kind, did a water change and I started giving them medicated food using API general cute. I also added prazi pro and melafix to the water. This appeared to stop it from spreading; it became confined to eight of my fish. However, it didn’t really improve the infected’s condition. In the meantime, I gave the affected fish a saltwater dip for two minutes. I continued this treatment for a about week.
Around day six, I lost two fish within 24 hours of each other. Before they died, something really strange occurred. I think their tank mates took it upon themselves to eat their eyes. They ate both eyes out of one fish but left her alive. They also ate one eye out of the other fish and let him live aw well. Neither of them had any other signs of being attacked. I’m unsure if they were attacked or if this disease ate away at their eyes. They both lived for another day and then died.
At this point I was freaking out and I pulled out Ruby Reef Rally - a medication I rarely use. I combined with Melafix, Primafix and continued with their medicated food. Finally, I began to see an improvement! Hope at last! Or, so I thought. Their condition was getting better and their eyes were clearing up. suddenly, three of the fish took a turn for the worst; two passed away.
Completely at my wit’s end, I pulled out my big guns. I added carbon to my filter and let it run for a few hours. I then removed the cartridge and added in Copper Power Green. Again, I opted to add melafix and primafix. The remaining three fish began to recover. I had one in a breeder box to stop anyone from eating his eyes. Because he began to look better, I released him from the box. He was fine for a few hours. Suddenly, I heard rocks moving in my tank. I turned on the light and saw him throwing himself against the rocks. I put him back in the breeder box and he passed within 10 minutes.
At this point, my heart can’t take much more. I was told this is probably some kind of severe bacterial infection. I was told to do a water change and switch meds. I was given API Fungus and API Furan 2. I did. This treatment is helping, but, there’s still a lingering film on the remaining three fish. On one of the fish, it looks like her pupil might permanently misshapen as a result of this. I have never dealt with anything like this at all. If anyone has any ideas as to what this was/is, I’m all ears.

 

Have you used live food or any other untreated fresh food (or introduced anything else like that)?

If not external, there must be stress involved. You said this happened after water change overnight. Can you think of any potential stressor involving water change? Poor conditioner, new water too different from the replaced, huge temperature difference? (New bully?)

Treating with everything can do a lot of harm. I don't know why melafix is recommended here. It has a softening effect on water, which is not what African cichlids like. (I used it on livebearers though, which is a similar situation.) Incorrect diagnosis and overtreatment may have triggered a vicious cycle. You say need to do more water change than 30% every two weeks.

 

Hey, I am very sorry about your fish/ I really want to try and help! Can you describe the "pimple-like growth directly on top of his pupil"? Is there only one bump or multiple? Are they spreading? Are they pits? Is there any color to it, like white or flesh-like or is it just protruding out from the scales? Does the cloudy pop eye come first or the pimple-like bumps? Are there any other symptoms? Does the cloudy eye seem to appear overnight? Also, can you give me a list of the type of cichlids that have the problems? Also what do you feed?

As for the missing eyes, your tank mates probably did eat them. Sometimes they won't even wait for them to die. It is the easiest and usually, the first part fish go to eat. Unfortunately, the fish that ate the sick fish are now more at risk, as you know. In the meantime, I think you should do more water changes, maybe 30% every other day. Pristine water will be beneficial in seeing some improvement.

Can you set up a QT tank? I think at this point, having a separate tank to medicate and separate healthy fish from sick fish will be helpful.

You've used pretty much every medication I could think of. I hope we can get to the bottom of it so we can start treating the fish with what might actually help; whether it is bacterial or fungal etc.

I dont say this lightly, but I am looking into TB as a prognosis. Usually, I would say this is developed pop-eye with a secondary symptom of cloudy eye, but the bump thing is really throwing me off. Plus the aggressiveness of how fast this is all happening.

 

MacZ A201 you guys have any ideas here?

 

I have a suspiscion but for that I need the full stock list from before fish started dying, the temperature, the hardness readings and what the fish are fed. And what fish exactly died.