strange bug thing on my fish

[me myself & I]

There is this strange bug thing on my foxfaces upper fin. It looks like a whitish colored potato bug. I'm trying to catch him so I can remove this. Any ideas what this may be? I post pictures later if I can catch him.

[Subrafta]

Sounds like a parasitic isopod. Here's some more info:

http://www.reefkeeping.com/issues/2002-05/rs/index.php
http://www.reefkeeping.com/issues/2004-08/rs/index.php
http://archive.reefcentral.com/forum...threadid=24445

[me myself & I]

Man that would be just my stupid luck! I just broke down and got live rock and now I probably have something that's going to destroy my tank if indeed that's what this is. I woke up early this morning to see if it was still there and it seems not to be, that could be good and bad! Thank you very much for all the time you must have spent finding all that info for me and I will keep you posted on the matter!

[Milamber]

How long can a parasitic isopod live if the fish are kept in a QT?

[STACKER]

AS long as the host is alive... Sorry! If you QT the fish with a cleaner and/or chemically treat it I'ds think that 2 weeks of observation would do it. I'd introduce an aggressive pod feeder or 2 for a month or 2 befoer adding any more fish too. Mandarins are good pod eaters but tend to pic off the small and slow pods. This critter is likely one ove potentially many so you should proceed with caution and an aggressive plan to eliminate all the nasty little suckers (pun intended)

[greenbean36191]

It depends. Some are obligate fish parasites and will die within a month or two and others can switch to scavenging in lean times and can live indefinitly without fish.

[gman0526]

It's going to be dependant on the amounto of food available for it.

[greenbean36191]

Pod eaters probably aren't a real effective way of dealing with these guys. They have actually been known to eat their way out of predators' stomachs, which usually kills the fish and doesn't harm the pod.

[me myself & I]

So basically this is the Terminator of aquarium pests. If this becomes a problem for me and I'm knocking on wood that it doesn't I'll have 2 options, 1. Throw of new live rock and buy new. 2. Take all fish out and find new home for them for who knows how long-months, years. Has anyone had this problem and dealt with it in other manners than basically destroying my tank. The bug that was on my Foxface was more of a whitish color and it really wasn't brown at all, is this good? Also where the bug was at seems like it didn't harm the area at all. Thanks!

[Agro]

I had a few in my tank that came on Florida live rock. I caught them easily with a net right after lights out.

FWIW mine were white, but I never caught one on my fish.

[Steven Pro]

Was your liverock you bought aquacultured from the Atlantic?

[Highlander]

FWIW, there was some discussion that interceptor might kill these things. I never saw any validating data though, but it certainly kills pods.
Alternately catching them with a net is possible, but the adults are fast!!.. Any juveniles can be caught using a turkey baster, IME. Best to try after lights out, using a lamp to the side of the tank to draw them onto the glass.

[latino277]

Just my $.02, Get one of those long shot glasses and at night put a fresh raw shrimp and see how many get on it the next morning... you may be able to remove them this way. I saw this on another forum some time back and seemed to work.

[jackson vile]

Don't worry, simply look for some fish, shrip, crabs, Nudis, ect that will eat that stuff.

The good news is that nature has an answer to almost every question, you just have to know where to look.

[STACKER]

Originally posted by greenbean36191
Pod eaters probably aren't a real effective way of dealing with these guys. They have actually been known to eat their way out of predators' stomachs, which usually kills the fish and doesn't harm the pod.

LOL Actually not funny but "funny". I got a visual of the "alien" emerging from a mans belly, covered in visceral tissue and blood from the movie. Sends shivers replacing my mandarin as the host... LOL

[yaksplat]

Originally posted by jackson vile
Don't worry, simply look for some fish, shrip, crabs, Nudis, ect that will eat that stuff.

The good news is that nature has an answer to almost every question, you just have to know where to look.

You're not going to find anything that successfully kills off a parasitic isopod. Manual removal is the only option. I removed 12 from my tank after getting them off of some florida rock. They liked to attach to my two clowns and my yellow tang. Every morning for two weeks, I'd prepare a freshwater dip and check if the fish had any clinging parasites. If they did, I'd catch the fish in a net and give it a dip. The isopod would let go most of the time. With the larger pods, I'd have to manually remove the isopod with tweezers after catching the fish. I'd do it on a wet paper towel. Two weeks of this and they all disappeared.


Good luck!! Don't give up!

[jeffbrig]

Originally posted by latino277
Just my $.02, Get one of those long shot glasses and at night put a fresh raw shrimp and see how many get on it the next morning... you may be able to remove them this way. I saw this on another forum some time back and seemed to work.

That was me!!

I originally set the shot glass w/shrimp up as a crab trap, but it proved equally effective at catching isopods.


Here they are congregating around the free food:


And a close up:


Just bait the trap, lean it against a rock, and wait 1-2 hours. They get in, but they don't seem to find their way out. I pulled 20-25 out of the tank in just a few evenings. I need to try the trap again to see if any more are lingering in the tank.

[me myself & I]

Man that's a good idea! I'm on bad pod watch right now and if I see any fish with one of those things on it I'll try your idea. Thanks! Steven Pro wanted to know if my rock was aquacultured from the Atlantic and the answer is no, it's all from the South Pacific area.

[TerryB]

Jeffbrig,

Cool photo and it definately caught something. You should contact Ron Shimek in his forum here and ask him to give you a positive ID on these buggers. I knew someone that had a species of parasitic isopods in their tank and Ron told them that the only way to get rid of them was to catch them at night when they attached to the fish. When the lights went on this species immediately left the fish and went into hiding. I don't know why Ron didn't suggest catching them in a food trap unless it doesn't work with that particular species. I am sure he would be happy to take a look at your photo and can probably ID it for you.

Terry B

[jeffbrig]

I did speak with Dr. Ron when I was originally trapping these. A species ID isn't possible, but he confirmed they are cirolanid isopods. Some cirolanids are obligate fish predators (i.e. feed ONLY on fish), and those probably won't take to a trap. These are the ones that must be captured as they fall off the fish, or starved out by leaving a tank fallow for several months. Other cirolanids can be harmless scavengers, or opportunists that will scavenge or prey on fish. I would imagine either of these is easily captured using the trap method above.

My rock came from the atlantic/gulf (aquacultured), which seems to be common for finding isopods.

[mokujin22]

Originally posted by jeffbrig
... Other cirolanids can be harmless scavengers, or opportunists that will scavenge or prey on fish....

yeah, about a year ago after addiing some Pacific live rock, these little guys started emerging and multiplying. i freaked out and stayed on isopod watch for several days/weeks. they were extremely fast swimmers and the only way that i could deal with them was to smash them with a long stick on the rock they were occupying, one by one. never saw them on any fish though and the facts that they were light in color and eventually all disappeared after about a month makes me think that they were the type that don't attack live fish.

tony.