Help with bristlenose plecos, strange wounds in the fins and emaciated bodies

[Acara19]

I have a 30 gallon tank housing a group of l144a plecos growing out, as well as an l183. I started with 4 l144a's. but I lost one for some strange reason. First, almost overnight, its tail and fins became torn to shreds for some reason, it just looked like something took a ragged bite out of the tail and fins, (there was even a bit of blood or some kind of redness) but then there isn't any predatory fish or anything in the tank, only plecos. it died the next day. now my l183 has the same thing, except this time it just looks like something took a clean, round bite out of its tail. this too happened overnight, same with the sunken belly, i've been checking on them daily and didn't notice this before. the eyes aren't sunken or anything, he just looks emaciated and then there's the strange wound in the tail. parameters are fine, and I do around 30% waterchanges weekly. temp is around 76-77. I did have a camallanus outbreak in my tanks a couple weeks ago, which wiped out my breeding stock of guppies in the tank, but as far as I know the species of camallanus worm that affects guppies doesn't affect plecos. I treated with levamisole, which cured the last guppy in the tank, but she still died from the stress of the treatment. the stress might also explain the first pleco death, but that still doesn't explain the wounds.

 

[Becca]

Photos?

 

[DiscusnAfricans]

Always a good idea to increase water change frequency and amount when something shows, you just have to be careful about disinfecting equipment if you have multiple tanks so you don't cross contaminate.

 

[Marz]

Might be a female and not ready to spawn. The males can get aggressive and beat up the females when they're not ready to spawn.

 

[chriscoli]

without pictures it's hard to tell, but sounds to me like fighting and stress from fighting. What sort of cover/caves/wood is in the tank?

I usually try to give "N" plecos at least N+1 hiding places and I try to offer multiple types of cover. for example, at least one spawning cave per male, plus wood or rocks nearby (often leaning on the spawning cave) that females can hide under as they approach it, plus some other wood and rocks elsewhere in another corner or two for any that aren't interested in interacting yet.