In Your Experience, What Have Been Some of the Most Problematic Fish?

[SilverArowanaBoi]

Hey, y'all! I just wanted to get your opinions on this. I know almost everyone has had at least one "problem" fish (e.g., one that was a pain to other fish, sickly, etc.) or fish species. I'm curious to see what y'all think are some of the most problematic fish you've kept.

For me, it was medium-sized angelfish. This may or may not be a surprise, but they were very nippy with each other, so I ditched them entirely because they were so hostile toward each other, and it was just annoying to watch, lol.

 

[Fallen_Leaves16]

Pseudogobio esocinus; never managed to secure a decent means of transporting and keeping them long-term when I was a kid. They'd always die shortly after collection; the few that somehow managed to survive long enough to be placed in a plastic tub with only a circulation pump, sand, and rocks often didn't live longer than 4 hours or so.
That was years ago, when I was quite little, and things such as filters were a somewhat novel concept. Most hardier fish did well in my setup, though, as the water was changed every day.
Always wanted to try keeping them again, but since I'm now in the US I can't get any, and within the last decade or so they seem to have mostly died out in streams surrounded by developing urban areas, based on the few short times I've been able to visit Korea again anyhow.

Pungtungia herzi were pretty tough to keep alive, until I realized that they take poorly to being removed from the water and often perish soon after.

I suppose Glyptothorax spp. and rheophilic Liobagrus spp. were tough to keep alive, too.

I don't think there's many fish that proved incredibly problematic to rear in captivity that I've kept- the majority of times I've had fish quickly die on me was when I made a mistake, or when the fish was ill to begin with. Then again, my memory's rather faulty; I suppose I'll remember more difficult-to-keep fish as I think about it more.

 

[abominus]

Hey, y'all! I just wanted to get your opinions on this. I know almost everyone has had at least one "problem" fish (e.g., one that was a pain to other fish, sickly, etc.) or fish species. I'm curious to see what y'all think are some of the most problematic fish you've kept.

For me, it was medium-sized angelfish. This may or may not be a surprise, but they were very nippy with each other, so I ditched them entirely because they were so hostile toward each other, and it was just annoying to watch, lol.

This may sound weird, but for me, it was Oscars. I know, I know—they’re hardy fish, yet somehow, I managed to kill four.

My first Oscar was a regular tiger Oscar. Unfortunately, it was already stressed and slightly bloated when I bought it. It couldn’t recover and died soon afterward.

The second one was a Latino Oscar (often called "albino" Oscar). It was doing fine until my Zebra Tilapia injured it. I quarantined it and treated it with medicine, but sadly, it didn’t make it.

My last attempt ended when I went on vacation. My dad overfed my two Latino Oscars, and both passed away. After that, I decided Oscars are definitely not my cup of tea.

 

[fishhead0103666]

This may sound weird but African butterfly fish, I just could never keep them alive long term. I’m thinking they’re aggressive amongst themselves when I wasn’t around? And quite possibly over crowding played a part.

 

[ken31cay]

My answer is a little broader in scope than what you asked, but my problem fish have been any fish that don't match my soft, low pH water. So any africans, especially wild caught, I have a hard time with due to having to chase their water parameters with every water change. South americans, on the other hand, are easy and it seems that nothing i cause to happen (high nitrate, blisteringly high ammonia, etc.) even phases them.

 

[Caveden]

Asian Arowana. So far i've kept 2 before, and both times each of the arowana kept killing and attacking my other fishes, including peacock bass, florida gar, datnoid. I do plan on owning another in the future since they are one of the most beautiful fishes anyone can own, and the price of asian arowanas have gone down significantly due to higher supply compared to the demand. hopefully i have more luck owning one that is more peaceful in nature.

 

[troublesum]

I have never really kept difficult fish but the problem i have is mostly with the amphilophus i always keep a solo in a 125 and i guess that makes them crazy and when ever i do tank maintance which is was 3x a week is now only 2x a week as i have so many scars and open wounds from him tagging me

 

[duanes]

When I have failed with a species, I find it is never the fault of the fishes, themselves, it usually has to do with some important part of the actual needs of the fish I have neglected or omitted.
Either the right amount of space is inadequate, the right water parameters were not met, or right current have not been provided for, or adequate O2, or water quality is just not up to snuff.

And most published aquarium criteria is just way too lenient and lax, compared to how most species lives in nature.

If the literature claims a soft water, low pH species will live between pH 5 and 7.5.
The reality is anything higher than 6.5 is pushing it.
Same if a hard water species will torate a pH as low as 7, it really means that species should have a pH aound 8.


If a species write up says a tank size as low as 100 gallons is adequate, it really means at least a 300 gal is minimum.

If a rheophillic species info sheet says that it will be fine with flow from a HOB filter, or an average canister is okay, it usually means a pump wth a gph of at least 1500 gph is minimal. in a 6 ft tank.. or just the opposite for stagnant water species.


If common aquarium memes claim a nitrate concentration of 20 ppm is tolerable, it usually means any concentration over 5 ppm can be dangerous, and over time diseases like HITH will develope in long lived species such as Oscars.

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjSqvHTyPOBAxXLnWoFHROXCG4QFnoECBoQAQ&url=https%3A%2F%2Fwww.journals.uchicago.edu%2Fdoi%2F10.1086%2F713252&usg=AOvVaw3wjKcEGjmgQiDil_lM_3aw&opi=89978449

 

[quikv6]

Banded leporinus....seemed to harass and kill tankmates for the fun of it. Now the nearly 12 year old curmudgeon is solo in the tank, thanks to his own sport.

 

[Deadeye]

Another vote on banded leporinus.
All around my favorite species, but it truly is one of the most unpleasant animals out there. Tankmates are a constant gamble of whether or not he accepts them.

Paracentropygon zonatus is another one. It’s a very pretty species of scorpionfish and a great nano reef fish, but I always had trouble feeding it. Generally they are easy to get onto frozen, but mine never did.