Hitchhiker ID

[Froggieboy]

Hey guys whatsup, a couple days ago i starter my 50 gallon and got some dry and life rock. And I saw a big bristle worm. After A while I saw something came out of the tail part of the body, some kind of isopod. A while after that there were 2! Now I think its a creoland Isopod but I just want to be sure. If thata the case Im not gonna put any "hosts" in and let them starve.

 

[Donya]

I can't confirm the exact type of isopod but it sounds like it was either eating the worm or a parasite on it. Because accurately IDing members of that group can be hard and most will cause problems (whether for your fish or other animals), it's safest to get rid of them.

The worm also does not look good; looks Eunicid-ish to me although I don't see a head which is the easiest thing to ID them by. Although there's nothing for scale, if that's a large Eunicid that's another very bad thing you don't want. Some very tiny Eunicid species are totally ok, but this doesn't look that small. Did the worm come out in-tact? If not, particularly if the head is missing, you'll want to keep an eye out for a regrowing worm.

 

[Froggieboy]

I can't confirm the exact type of isopod but it sounds like it was either eating the worm or a parasite on it. Because accurately IDing members of that group can be hard and most will cause problems (whether for your fish or other animals), it's safest to get rid of them.

The worm also does not look good; looks Eunicid-ish to me although I don't see a head which is the easiest thing to ID them by. Although there's nothing for scale, if that's a large Eunicid that's another very bad thing you don't want. Some very tiny Eunicid species are totally ok, but this doesn't look that small. Did the worm come out in-tact? If not, particularly if the head is missing, you'll want to keep an eye out for a regrowing worm.

Thanks for replying!
The worm died because of the injuries and I took it out. Havents seen those isopods since. I am just gonna starve them by not adding any fish or critters in the hope they'll die off. And in about 2 months Im gonna make a small trap to see if they are still alive.

 

[Colin_T]

We used to find things like that in fish we caught. We called them fish doctors but they are parasites that crawl inside a fish's mouth and feed off blood. Kill any that you see.