Plecos dying with foul smelling odor upon removal

[Isaiah75]

Have you tested your water?

Yes

If yes, what is your ammonia?

Zero

If yes, what is your nitrite?

Zero

If yes, what is your nitrate?

<10ppm

If I did not test my water...

...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

31-40%

How frequently do you change your water?

Every week

If I do not change my water...

...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

I need of help! I’ve had two places die within a week of each other. When I removed them from the tank they both had similar foul odor coming from their rectum. I have medicated the tank w Metrocleanse and Expel-P. Is there anything I’m missing before I lose the rest of my plecos in the tank?

 

[Deadeye]

Did they look/act off before dying? Anything to indicate infection?
Not many fish (or any living thing) won’t smell bad when they die.

 

[Isaiah75]

No, they both seemed normal. And yea, I get that but just found it odd that they both had the same discharge and it smelled the same. I’ve been keeping plecos for a few years now and haven’t had they smell like that when I pull dead ones out of my tanks.

 

[Deadeye]

Have the problems stopped since you dosed the tank? Both of those meds should cover you on parasites.
You mentioned discharge - did anything physical come out of the plecos or just smell?
Are any other plecos showing signs of anything? For now I think the best you can do is monitor for if anything changes.

 

[Isaiah75]

Just a smelly liquid. Nothing solid came out. And yes, the rest of them look and are acting normal as of rn. But so was the one that passed away yesterday. I’ll keep an eye on it and keep dosing as instructions say. Thank you.

 

[Fallen_Leaves16]

What species? How old? Origin? Diet? Has anything changed within the last two weeks?
Do you have any pics of the dead fish, by any chance?
Were their rectums swollen or prolapsed in any way?
How long were they sitting in the tank before getting removed?

 

[duanes]

What size tank?
How many Plecos?
How old are they?

 

[Isaiah75]

Replying to both Fallen_Leaves16 and duanes at the same time
They’re all in a 75 gallon with plenty of caves and wood work to hide in. I’ve got two green phantoms, one blue phantom, two Bristlenose, one xingu Royal, one marble Sailfin, one vampire and three geo altifrons. The plecos range from 2” to 7”. I had another albino Sailfin and a golden vampire. Those two are the ones that died. Both with in the size range I mentioned above. I’m growing out the geos they’re 2-3 inches rn and will move them to a larger tank once big enough and same for the sailfins. I do not have pics unfortunately and yes, rectums were slightly prolapsed. They weren’t in there for more than a day cuz I check all my tanks every night during feeding. I feed the tank Xtreme Scapers, beef heart, vibra bites and community flakes.

 

[duanes]

Plecos can be quite territorial, especially when mature, and will fight if kept in a relatively small box. And I consider a 75 gal tank small, for Plecos that are already 7". For me that size tank might only be large enough to hold 2 plecos.

I would also be stingy with beef heart (I wouldn't feed it at a all), many fish have a hard time digesting the fats in mammalian meat, and that could lead to intestinal problems.
A clue might be the foul smelling discharge. How soon after feeding the beef, did they die?

 

[Fallen_Leaves16]

I do think the beef heart was a major factor in the deaths- I find it unlikely for a foul odour to result from feeding merely pellets and flakes and such, especially if they had not been sitting in water for long.
As Duane pointed out, fish for the most part are unable to properly process much of what is in the organs of terrestrial mammals, and excessive feeding can lead to impaction and death. Used to kill a large amount of fry as a result of feeding them too many meaty things.
The Leporacanthicus is most likely to be attracted to meaty foods, and as such, I wouldn't be too surprised if it died from gorging heavily on beef heart and dying; though I do wonder why the galaxias isn't affected. Pterygoplichthys are greedy blighters; wouldn't be too surprised if they too overate 'til they died.
I don't know if territorial behavior would warrant sudden death, especially if the fish were not heavily damaged. And the sheer differences in size and body shape makes conflict, in my opinion, less likely to be a major problem. Could always be proven wrong, though.
Any signs of inflammation or bacterial infection? Could always be a possibility, though more unlikely than not, I'd think.