Isopod ID and possible removal

[Power_t]

I got a couple of new pieces of live rock in a container right now with what I've identified as (Cirolana harfordi).

Harford's Isopod, Cirolana harfordi

It is a Cirolanid and info is very scarce but it's supposedly not harmful to fish and instead feeds on detritus and small crustaceans. Here's an old post with similar information about it: https://www.reef2reef.com/threads/i-know-it’s-an-isopod-but.358988/#post-4452724

Here's a picture of one of the Isopods I took out of the rock:

Here's the thing though, is it worth it to risk it?

Any sure way to completely remove them? It's only 4 pounds and in a container. I was planning on using the rock to seed a new dry rock tank, so as long as I can use the bacteria I'm satisfied.

 

[TriggerFinger]

The eyes don’t have the “evil” look, it might be a good guy. Here is a good description by lion fish lair to determine if it’s the parasitic pod or not. And this is the thread it’s from https://www.reef2reef.com/threads/h...cirolanid-verses-sphaeromatid-isopods.251779/

//CIROLANID VERSES SPHAEROMATID ISOPODS.

When you know what your looking for, telling the difference between a Cirolanid (bad) versus a Sphaeromatid (good) becomes a lot easier. It's all in the eyes.....
The eyes of the Cirolanid are generally closer together and towards the front of the head. They always look angry because of the slant of their eyes. Think of them as needing to look forward to "capture" it's prey.
The Sphaeromatid eyes are generally more to the side of the head. They always remind me of baby seals with their big black harmless looking eyes. Looking at the side by side pictures I've included of both isopods may help with this "visualization". smile emoticon
Sphaeromatids also have the common name "Roly Poly" as they, unlike the Cirolanid, roll up in a defensive position when they feel threatened. The Ciralonids cannot do this. Think of it like this: the Ciralonid is mean and will never back down from a fight. The innocent little Sphaeromatid rolls up in a tiny little ball saying "Please, don't hurt me!".
Where you find them may also help decipher which is which. If it's attached to your fish, it's probably pretty safe to say it's a Cirolanid. If there are a few scurrying around when you lift up a rock, lean towards it being a Sphaeromatid.

 

[Power_t]

The eyes are very misleading, but it doesn't curl up into a ball and I can't spot the alleged male individuals that have the two tails at the rear so I'd say it's not it.

Definitely not the Cirolanid in the picture either but as I understand the Cirolana family is very extensive and it's near impossible to determine if it's a good one or a bad one.

Thinking about going the safe route and just getting cultivated rock instead.

 

[stanleo]

My opinion. I don't have any of the good ones like this and my tank doesn't suffer for it. I would get rid of as many as possible and not let it in the tank.

That said, it does look like one the good guys to me. I still wouldn't let it in though. The bad ones are really bad for fish.

 

[Power_t]

Update: I got in touch with the store, they keep this rock in their biggest system along with both fish and corals. The Isopods have been there a long time and they have never had any problem.

For now it's gonna go into a new temporary frag tank, I will keep an eye on any fish that goes in there and will update this thread if I notice something.

 

[Power_t]

Just updating on this: I've had them in a frag tank with 3 anthias and 1 meiacanthus for close to 3 months now and everything's fine.

As with everything in the hobby, this isn't concrete proof that they're not predatory, but at least I can say they're not strictly predatory. I've seen them eating formula 2 pellets and most likely can survive on detritus and leftovers.

Hopefully this thread can be of use to anybody looking for info.

 

[reefinatl]

I found a similar, maybe even identical one in my tank after some gulf rock. I didn't want to even begin to try and trap that thing. No issues 2 month in though. Eyes like that generally indicates predator, but heck almost everything in our tanks is a predator of something.

If I had caught it like you did I wouldn't have put it back though, you are braver than me in that regard.