Help, random loach deaths

[Ikonic]

I have had my 56 gallon tank up and running for coming up on two years, tank has not had issues for over a year until monday when both of my loachata boatias died and one of my two clown loaches died. None turned pale and seemed entirely healthy until moments before they died. My tanks numbers are all great and im stumped. Weekly water changes of 50% with no temp fluxuation.

Stock:


Two bristle nose plecos (small babies)
Three cory catfish
One black ghost knife (new a month ago)
One golden gourami
One iridescent shark (small)
Three red fin tetra
One half beak gar
Up until monday two loachata boatia and two clown loaches that had been with me almost two years.


What could cause this sudden death?

 

[Neo287]

That is odd but it does happen. Did you notice any strange behavior before they passed?

 

[Ikonic]

Not at all. Thats why i am so puzzled. Never even looked unhealthy.

 

[Neo287]

You mentioned in your first post you had a recent addition to your tank, the one black ghost knife(new a month ago). I know most do not, but did you happen to quarantine the new fish before adding it to the tank? If not, it is currently acting normal(Swimming, eating, etc)?

Although rare, sometimes a new fish can introduce something to your tank and appear unaffected by it, acting as carriers, and pass it on to other fish that are more susceptible to the disease.

Another possibility is new contaminated ornaments and/ or live plants if any were added recently. From my understanding, loaches are a bit more sensitive than some of the other fish we keep.

I know it can be frustrating not knowing the cause of death and how you can fix it should it happen again. I have been in the same situation before. All fish in the tank appear healthy then out of nowhere one up and dies for no obvious reason Sorry for your losses and I hope everything stays well for you.

 

[Ikonic]

My ghost knife is currently the healthiest in the tank. I added new drift wood a while back but i always boil it for over half an hour before i use it.