Isopods in Indonesian life rock - ID?

bcardoro · Feb 28, 2022

Hi!

I bought several kg of indonesian live rock for a new reef tank built. The rock was awesome, it was just two days out of water, it was very clean (suggesting it was collected from relatively deep water) and it looked full of live. Among all the stuff I found (many crabs and worms arrived death), I have noticed the presence of isopods which I have been catching night after night. I am not sure if they are one of those bad cirolanid isopods.

Has anyone in this forum dealt with this kind of isopod (see pic attached)? Does anybody know if this kind of isopod will attach to fish?

Many thanks in advance!

bcardoro · Feb 28, 2022

elysics · Feb 28, 2022

Certainly look like the bad ones.

Is that new build still fishless? Maybe just starve them out for a few months and keep catching them until they are gone

Borat · Feb 28, 2022

elysics said:
Certainly look like the bad ones.

Is that new build still fishless? Maybe just starve them out for a few months and keep catching them until they are gone

Look at their evil faces - clearly trouble makers...

Come on man, you might have come up with a better advice here or just say you don't know a piece of potassium here

elysics · Feb 28, 2022

Borat said:
Look at their evil faces - clearly trouble makers...

Come on man, you might have come up with a better advice here or just say you don't know a piece of potassium here...

I said they look like the bad ones... As in probably cirolanid, not the main other mostly harmless ones. Big, forward/upward pointing eyes, oval body.

And afaik, the best course of action if you don't want to nuke everything is to go fallow and/or catch every single one until they are gone

ying yang · Feb 28, 2022

How to tell the difference between "good" and "bad" Isopods (CIROLANID VERSES SPHAEROMATID ISOPODS)

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...

www.reef2reef.com

Little information here for you

ying yang · Feb 28, 2022

http://reefkeeping.com/issues/2002-05/rs/

Article here,good luck ^_^

bcardoro · Feb 28, 2022

elysics said:
Certainly look like the bad ones.

Is that new build still fishless? Maybe just starve them out for a few months and keep catching them until they are gone

Hi elysics, thanks for your reply. Yes, it is still fishless. The rock has been in my system for 2 months now and it is completely cured. It is a 2-tank system. The rock is in the "frag" side of the system, which is bare bottom, and then I have the "display" which has sand. I will see how I manage the system to go fishless for a couple of months more, but I would like to add a few corals.

bcardoro · Feb 28, 2022

ying yang said:
How to tell the difference between "good" and "bad" Isopods (CIROLANID VERSES SPHAEROMATID ISOPODS)

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...

www.reef2reef.com

Little information here for you

ying yang said:
http://reefkeeping.com/issues/2002-05/rs/
Article here,good luck ^_^

Thanks for your reply @ying yang. I did read those articles. The isopods I have certainly have that "evil" face that the articles mention. However, regarding the eyes, they are in an intermediate position: not very close one to each other, nor completely separated. Thats why I decided to share my pics.

ying yang · Feb 28, 2022

reefnook said:
Thanks for your reply @ying yang. I did read those articles. The isopods I have certainly have that "evil" face that the articles mention. However, regarding the eyes, they are in an intermediate position: not very close one to each other, nor completely separated. Thats why I decided to share my pics.

Yeah understand what you mean ,I take it you have removed some from the tank and into a container,so If so have you tried poking them with something to see if they curl up into a ball as this is one of the characteristics that a bad Ciroland isopod cannot do.
My guess would be from them 2 pictures you shown above is they are female sphaermatid isopod from eye positions and the back " tail" part but on your picture cannot see of got any " antenna" on front but this is just my guess from reading above article and @lionfishlair thread they made and I shared above but I've tagged them and they should be able to advise you better as I'm no expert and as I say,just a guess
Good luck

ying yang · Feb 28, 2022

@Lionfish Lair
UMMM SEEMS I CANNOT TAG THEM SORRY

bcardoro · Mar 1, 2022

Little update: Yesterday I tried to catch a few isopods using some of the information given in http://reefkeeping.com/issues/2006-02/bp/index.php. I am still freaking out haha.

That's what I did. I soaked a piece of bait shrimp in a cup of saltwater from the tank and once the shrimp was unfrozen, I took a bit of the cloudy, stinky water (with no meat, that's important) and I throw it into the tank. BOOM! Even with the lights of the room on, they went crazy. And I just threw like 30ml. I was not aware of how many isopods were hidden inside the rock. Specially the big ones, which I rarely saw when standing at night with a flashlight. With this bait they showed up and I could take them out using Julian's thing device for feeding corals and fish. I had to cut the tip, otherwise the "big" isopods did not go through the hole. Another important tip: once you suck up an isopod, you need to take the device out of the water quite fast, since they tended to swim towards the tip of the device.

I took out like 100 isopods with this method in a matter of 1h. I put them on a container and just to satisfy my curiosity, I fed them with a portion of shrimp. It was scary... this bugs are worst than piranhas. I even saw how a single isopod killed a bristle worm which was also in the container. He literally gutted him.

I will post a video later eating shrimp. Next time (I hope there is not next time honestly since I hope most of the isopods are already out) I will shoot a time-lapse, since they ate 1cm3 of shrimp in just 3 minutes. Definitely, these isopods are predatory on fish and on whatever has meat actually.

One thing I noticed is that the isopods were pretty translucent, which I think it is a good sign. Once I fed them with shrimp, they acquired an orange coloration (I could see the food inside their body). This means that inside the tank they have no food and with the method just described combined with they have no food source, I hope I will fix this problem soon or later.

B

bcardoro · Mar 2, 2022

As suggested in other sites, bad ones can not roll up in a "ball"

Here they are finishing the meal, before being thrown at the sink.

ying yang · Mar 2, 2022

reefnook said:
As suggested in other sites, bad ones can not roll up in a "ball"

Here they are finishing the meal, before being thrown at the sink.

Infestation hey.looks like you got lots and lots pffft

bcardoro · Mar 2, 2022

ying yang said:
Infestation hey.looks like you got lots and lots pffft

Yep, as I said, I took around 100 isopods out. Today or tomorrow will go "iso-fishing" again. Live rock was perhaps too live haha. I wanted to create another post with my experience with this shipment of live rock, but for the time being... Let me explain it was 105 kg of live rock in total. It arrived very fresh, just 2 days shipping, so I expected almost everything. And indeed, I found everything: all types of worms (including couple of bobbits), crabs, pods...

Anyway, I had room (this new system is 1 display + 2 frag tanks each one as big as the display) for performing various inspections. And so I am doing. When I was unboxing the rock I was very careful. I inspected piece by piece. The final result after 1st inspection, the salad attached below. I put the rock in the sump. After a couple of days, I did a 2nd inspection, piece by piece again, and I moved the rock to the display (which had not the substrate yet and I filled up with water temporary). Then again, 3rd inspection piece by piece, and I moved it to the frag tank. And it is sitting there for now.

The salad:

The devil (look at those tweezers!):

ying yang · Mar 2, 2022

Yes indeed ,your live rock is teaming with life ^_^
I love all the micro fauna and bugs and that as find fascinating but some of them if I'm honest creep me out a little ha ha
Little mm pods are one thing but when get to 1cm isopods and bigger and the unknown of what it could or couldn't be kicks in then get a little concerned,I went thr dry rock route but see often others say using live rock and getting all the good guys on tje rock helps tank tremendously and with a little work can identify and remove the bad guys.
Anyway good luck and enjoy and get yourself on next round of " iso-fishing " ^_^

Borat · Mar 2, 2022

reefnook said:
As suggested in other sites, bad ones can not roll up in a "ball"

Here they are finishing the meal, before being thrown at the sink.

Murderer!!!

Apotack · Mar 2, 2022

I’ve had success using a trap made from a water bottle. Cut the top off, flip it over and secure with the narrow opening facing into the bottle bait the trap. It’s difficult for them to get out once they are inside the trap.

bcardoro · Mar 10, 2022

Apotack said:
I’ve had success using a trap made from a water bottle. Cut the top off, flip it over and secure with the narrow opening facing into the bottle bait the trap. It’s difficult for them to get out once they are inside the trap.

I tried this for a couple of hours at night, but I was a bit worried about leaving the trap overnight. Over that period of time the trap did not catch any isopod. The best method was using Julian's thing from two little fishes.

Apotack · Mar 10, 2022

reefnook said:
I tried this for a couple of hours at night, but I was a bit worried about leaving the trap overnight. Over that period of time the trap did not catch any isopod. The best method was using Julian's thing from two little fishes.

What’s you concern about leaving it overnight? i left mine overnight i would find them in the trap in the morning. I continued for a few weeks after I wasn’t catching anymore just to make sure I had them all. In total i had less than a dozen.