FW mollies converted to SW, now have ich?

[Coelli]

Late last week I bought a few FW mollies, acclimated them to saltwater, and added them to my display refugium. Today a couple of them have some white spots on their fins and one looks to have a cyst on her side. Unfortunately the others are dalmations so it's nearly impossible to tell if they also have the same. I did not QT them because it was my understanding that FW ich cannot survive in saltwater.

None of the fish in my display (last fish added a few months ago) have ever shown any sign of disease and are all fine.

It's entirely possible/likely that the mollies picked up the ich, if that's what it is, from my tank. What I'm wondering is if it's possible that it's freshwater ich and won't be able to complete its lifecycle?

Just trying to figure out my plan of action here. Unfortunately I'm not equipped to move all of the fish out from the display, and would have to remove rocks to get to some of them (watchman, yasha) even if I had somewhere to put them. I also have a green mandarin and scooter dragonet which further complicates things. Since none of them have ever shown any sign of disease I'm not sure it's worth trying to treat them and let the system go fallow.

If it is marine ich, will having symptomatic fish in the system increase the chance of my normally ich-resistant fish being overcome? I could separate the display fuge for now.

Any thoughts?

 

[scuzy]

have any of your fish in tank ever been quarantine? they could be silent carriers and they don't show it cause they aren't stress.

 

[ThRoewer]

Well, these mollies have never been exposed to Cryptocaryon irritans and therefore have no immunity against it like obviously your existing fish in the DT.

Simple solution: bring them back to freshwater for a month or two so that they get cleaned up and develop immunity. After that they can go back and hopefully won't show ich anymore.

This is kind of proving that you may actually be able to use freshwater mollies as "canary" to test if your system has ich.

 

[Coelli]

have any of your fish in tank ever been quarantine? they could be silent carriers and they don't show it cause they aren't stress.

Yup, this is what I suspect too.

For reference in my DT:
Pair of juvenile clowns
Yellow Watchman
Royal Gramma
Lyretail Anthias
Yasha goby
3 ORA neon gobies
Green Mandarin
Starry Blenny

The watchman was the first fish and has been in the tank for 15 months. The neon gobies are the most recent in the DT from a few months ago.

The scooter blenny in the display fuge is the most recent saltwater fish overall and was added a couple of weeks ago. He's the only fish in the DF other than the mollies.

Well, these mollies have never been exposed to Cryptocaryon irritans and therefore have no immunity against it like obviously your existing fish in the DT.

Simple solution: bring them back to freshwater for a month or two so that they get cleaned up and develop immunity. After that they can go back and hopefully won't show ich anymore.

This is kind of proving that you may actually be able to use freshwater mollies as "canary" to test if your system has ich.

Yes! If nothing else, there's that.

I do have a 10g I could set up for them if I can find a heater. I'll look into how to acclimate them back over. My family is going to give me a hard time about setting up a third tank, lol.

 

[Deinonych]

My family is going to give me a hard time about setting up a third tank, lol.

Only three? Count yourself lucky.

 

[Coelli]

Only three? Count yourself lucky.

Haha! Yeah, I know...

I'm keeping an eye on the DT; my anthias has been seeking out the cleaner gobies. It's possible the scooter dragonet is my vector. He's in the display fuge with the mollies, and he was the last to be introduced. If that's the case this could be bad. :| He looks fine, but...

For now I've shut down the connection between the display fuge and the sump to prevent the parasites from the mollies travelling to the DT until I can get them out. I hope I'm right that my fish were resistant and that disaster is not impending. I can get some of my fish out of the DT, but not all.

 

[snorvich]

Ich does not have to present visibly in order to be present.

 

[Coelli]

Back with an update - a cautiously optimistic one.

I bought 5 mollies last Friday from PetSmart and two more Sunday from another store. One died from each batch.

The 4 female mollies (batch 1) started showing signs of ich on Monday. The cysts burst over Wednesday night and they look much better today. They're all eating and acting normal.

The male from the second batch/local store is fine, no sign of ich, and is harassing the females.

None of the fish in my display are showing any symptoms.

I haven't been able to find anything definitive, but did find an article on freshwater ich that said "The free-living tomonts and theronts cannot survive in water with more than a trace of salt." So I am hopeful that perhaps it was freshwater ich that came in on them after all; they had a ton of cysts, and if my tank was that heavily infested I can't imagine the male molly wouldn't be symptomatic by now.

I'll update if anything changes or hopefully to say that the mollies (and my reef fish) continue to be healthy and everything is okay!