Are these harmful copepods

[Gianlucabinetti]

Looks like my predatory tank got some copepods I was wondering if these were harmful or were the good kind I know it’s pretty rare to get the harmful ones, but I just want o be safe they move a lot so I know that it isn’t ich

 

[Deadeye]

Not sure if any copepods are harmful.
Definitely not ich - that only appears on the fish.

 

[Gianlucabinetti]

Not sure if any copepods are harmful.
Definitely not ich - that only appears on the fish.

Thanks

 

[FJB]

Cant see them.
There certainly are harmful copepod species. Parasitic species are not uncommon. Among them Ergasilus (many species) are known as gill lice.
I am not saying this is what you have, just that some copepods are undesirable.

 

[duanes]

There are also many species of Lernea that parasitize fish, some species specific (on cyprinids) some more generalists.
They are easily introduced when using live feeder fish like minnows or goldfish.
These were brought in on wild caught tetras


To get rid of adult Lernea, I had to remove them with a tweezers.

To stop juvie parasites from surviving, I used 3.5lbs of rock salt per 100 gallons to bring salinity up to over 3 ppt (parts per thousand).
That salinity however: does not kill adults, hence the need to physically remove by hand.