Bio-Cube & Eunice Worm


New member
Currently My tank is in my bed room. I plan to move it up stairs to my living room. I have a eunice worm, but it was small and did not cause problems, only eating mushrooms and the odd zoas. Recently I added a Fishers pygmy angle and it has been attacked three times by something. The most recent is a small semi circle bite out of his dorsal fin. The attacks are happening at night. My rock work has a cave space behind it where the fish like to sleep. I hear sounds at night like scraping stones and sometimes a loud click like stone on glass. I have spent many nights up late looking for critters that make the sounds and attacking shrooms, zoas and fish. I need to find the bad guy a.s.a.p. to save my fish and so I can move my tank.


Premium Member
Ouch! I don't think it's the worm just because the bite mark would look more like a tear or slit rather than a semi-circle. Good luck on finding the culprit.


New member
I might be mistaken, but I believe most Mantis Shrimp are diurnal. Clicking at night is usually hermit crabs banging their shells on the glass or a pistol shrimp...


The Hardy Mongolian Pony
Most are but just because they are diurnal doesn't mean they won't make clicking noises at night. I've lain awake at night listening to my G. chiragra pound away. I'm not saying that it's a mantis and in all manner of fact it probably isn't but just keep in mind that it's possible.

I would take the fish and inverts out of the tank, set them in a QT or ask a friend to hold them for awhile, and check the fish to see if it's not just a tankmate. Just get them out of that tank and see what happens, if they don't receive any bite marks then it's probably something in the rockwork/sand.


New member
It sounds like a mantis or a crab. If you only have a bio cube I would tear it apart and find the culprit. Especially if your planning to move it anyway. You could even do a fresh water dip on your rock until you find the critter if you can not locate it by site. If not it will kill your fish. Definitely not your clown fish. Look in all rock crevices. Crabs are hard to locate because they are camouflaged very well. Crab would be my bet.