Finding half eaten fish

[2loud]

I have a 55 gal community tank over a year old. Tank parameters ammonia 0, ph 6.8 to 7, nitrite 0, nitrate 5 or less. Temp 77f. I am finding fish half eaten. I have a mix of black, ember and neon tetras, a few zebra danios,5 Cory's and a 3 inch pleco, and 5 guppies.I also have 2 german rams, one dominant, one submissive ( so dominant doesn't bother other fish.) Fish have been together at least 2 months since last additions. Tank has live plants.I do weekly 30 to 40% water changes.and have 2 cascade 1000 filters with pre and post foam filters to protect smaller fish from intake injury or flow issues from outlet. I am wondering if the dominant ram would kill tankmates? I find one or 2 everyday this week half eaten, but not rotting. No fish in the tank is greater Than 3 inches, and I see no aggression in the tank when I watch it for 2 or 3 hrs each evening. I am stumped. I have had fish for 30 years and never had this happen. Not finding near filter inlets, just floating at top Looking for advice

 

[Rocky998]

It could be that your fish are dying and then the pleco or corydoras come along to snack on them, leaving the body

 

[2loud]

No one seems sick, and none are currently over 8 months old. No signs of stress. It's different fish as well. 1 cory, 2 neon, 2 guppy, 1 zebra ( they are oldest) have been found over about a week, mostly just the head left.

 

[GaryE]

Even gentle Cichlids announce breeding by killing carefree tankmates who come too close. Could your Rams be pairing? The pleco could be gnawing on the unlucky ones who got caught up.

 

[Rocky998]

Hopefully someone else can help... Idk. But I will say that corydoras on gravel can hurt them. They naturally filter feed by putting sand through their gills and they like to dig. Their barbels can get messed up in gravel

 

[2loud]

No one seems sick, and none are currently over 8 months old. No signs of stress. It's different fish as well. 1 cory, 2 neon, 2 guppy, 1 zebra ( they are oldest) have been found over about a week, mostly just the head left.

Although I can't rule it out . My fish generally live alot longer than this.

 

[2loud]

Even gentle Cichlids announce breeding by killing carefree tankmates who come too close. Could your Rams be pairing? The pleco could be gnawing on the unlucky ones who got caught up.

I don't think so, they usually stay far apart. Also hard to tell sex. One is very bright [ the dominant one, and I believe male] the other is very dull almost grayish, but no pink Belly and the dorsal fin is very similar to the other ram. If they are mating, there has been no chasing that I have seen, and they generally avoid each other in distant caves. Again, possible though.

 

[2loud]

I don't think so, they usually stay far apart. Also hard to tell sex. One is very bright [ the dominant one, and I believe male] the other is very dull almost grayish, but no pink Belly and the dorsal fin is very similar to the other ram. If they are mating, there has been no chasing that I have seen, and they generally avoid each other in distant caves. Again, possible though.

I appreciate the response though.

 

[GaryE]

It's disease or murder. You don't have any obvious killers, by species profile. But if it's disease, you have no symptoms. I think you are just going to have to observe. The ram has the bulk to do it, but they are usually not killers. I once had a zebra danio, of all fish, that went on a killing spree. I had a few hundred that didn't though. Very perplexing.

 

[2loud]

Observing every night but agree it's frustrating. Will keep watching. Usually a morning find, but not sure it mean's anything. Still watching for other signs. Thank you for yor response, very appreciated.

 

[AdoraBelle Dearheart]

Observing every night but agree it's frustrating. Will keep watching. Usually a morning find, but not sure it mean's anything. Still watching for other signs. Thank you for yor response, very appreciated.

Any chance of setting up a camera to observe the tank? Maybe with a blue light overnight, in case the killer is nocturnal.
What species of pleco?

 

[2loud]

The pleco is a rubberlip. Good idea on camera, as it does seem to happen at night more often than not.

 

[GaryE]

Chaetostoma milesi... or not, it shouldn't be a hunter. Every fish forum has a couple of nerds like me who like to use Latin names and dislike trade, English ones. There is one rubber lipped pleco, and 3 rubber plecos, and none of them are technically plecos. They all grow to different sizes. But they all seem to be algae eaters who occasionally scavenge. That fits the pattern of what you're seeing.

Every other fish you have is a daylight feeder. So the overnight killing would only be the Chaetostoma and that just doesn't fit. I would start looking in the day, for disease. Real hardcore quarantine tank keepers say 3 months is the limit. I QT for 6 to 8 weeks. So you are still in the zone, as unlikely as that is too.

It's a mystery.

 

[2loud]

So I may have answer. The big ram hides inside a large hollow tree in the tank. I found the smaller fish chasing each other thru various openings in the tree agitating him. I think he has been defending his home, and then the others are scavenging the injured/ dying ones. Best observed behavior. No deaths this morning.

 

[Slaphppy7]

The ram does sound like the culprit

On another note...you are keeping soft water fish (tetras) and hard water fish (guppies) in the same tank...what is your source water hardness?

Not sure where in Texas you are located, but we have soft tap water where I live