Isopods- always bad?

[Tired]

Edit: did some googling, and I think it's a Cirolanid. No luck on the traps. Anyone had luck trapping these, and anyone know how long they live without food? 

 

Just spotted some sort of gray isopod in my tank when I snuck over with a flashlight. It froze when I put the light on it, and I did actually manage to catch it in a turkey baster, but it was way faster than expected and swam out the open end before I could get my finger over it. It was about 1/3" long, and I think it had a black or dark gray head. It didn't look quite as plump as those little monsters that latch onto fish, it was shaped more like a sea slater/dock roach/wharf roach. 

 

Not all isopods are trouble, right? There's, what, hundreds of species, and I can't imagine they're all predators. 

 

If it is one of the predators that latches onto fish, how long can it live without a host? I'd imagine it'll starve eventually.

 

I have zoanthids and rock flower anemones, and haven't seen any of them look eaten. Sometimes the zoas are closed temporarily, but from what I gather, that's a fairly normal part of having zoas. 

 

I made some impromptu miniature bottle traps out of pill bottles and some bits of jug plastic that I rubberbanded into funnels. Also superglued my fingers very heavily before learning that, for whatever reason, superglue doesn't seem to want to set when you use it on water jug plastic. One trap is floating because I ran out of weights, one is sunk but standing upright because I'm too tired to try and distribute the weights (cut-off stems from frag plugs) evenly inside the trap somehow. If these don't get it, I'll think of something better when it's not the chunk of time between midnight and 1am.

 

Note to self: handle gel superglues only, NOT liquid superglues, after 10pm. 

[Ratvan]

On 11/17/2019 at 7:06 AM, Tired said:

Edit: did some googling, and I think it's a Cirolanid. No luck on the traps. Anyone had luck trapping these, and anyone know how long they live without food? 

 

Just spotted some sort of gray isopod in my tank when I snuck over with a flashlight. It froze when I put the light on it, and I did actually manage to catch it in a turkey baster, but it was way faster than expected and swam out the open end before I could get my finger over it. It was about 1/3" long, and I think it had a black or dark gray head. It didn't look quite as plump as those little monsters that latch onto fish, it was shaped more like a sea slater/dock roach/wharf roach. 

 

Not all isopods are trouble, right? There's, what, hundreds of species, and I can't imagine they're all predators. 

 

If it is one of the predators that latches onto fish, how long can it live without a host? I'd imagine it'll starve eventually.

 

I have zoanthids and rock flower anemones, and haven't seen any of them look eaten. Sometimes the zoas are closed temporarily, but from what I gather, that's a fairly normal part of having zoas. 

 

I made some impromptu miniature bottle traps out of pill bottles and some bits of jug plastic that I rubberbanded into funnels. Also superglued my fingers very heavily before learning that, for whatever reason, superglue doesn't seem to want to set when you use it on water jug plastic. One trap is floating because I ran out of weights, one is sunk but standing upright because I'm too tired to try and distribute the weights (cut-off stems from frag plugs) evenly inside the trap somehow. If these don't get it, I'll think of something better when it's not the chunk of time between midnight and 1am.

 

Note to self: handle gel superglues only, NOT liquid superglues, after 10pm. 

If you rough up the bottle plastic with sandpaper before gluing it helps the glue to adhere 👍