Parasites in Frozen Food?

[Jack22]

So, I'm not even sure if this is possible or not. LFS says there is no way it was from the frozen food. Here is my experience, I'm wondering what everyone else thinks.

About 6-7 months ago I added a Moorish Idol to may tank. My tank was fairly new (about 2 months maybe) and I had 4 other fish that were all doing well. Moorish had been at the store for a little over a week, no sign of infection and was eating fine. I did not QT him. Had trouble getting him to eat so I purchased a frozen food that was recommended to me. Within two days my entire tank had Ich. By the time I was able to get a QT tank set up, all the fish had died except one. Now I QT all my fish for 30 days.

Fast forward. I had a yellow tang, salifin tang, and a copper banded butterfly in QT for about a week. Everyone doing fine, but the copper band didn't seem to want to eat much. So again I tried the same food. Within two days they all had Ich. I tried to treat with copper, but before I could get it up to the proper strength they were all dead.

now I know I dealing with fish that are highly susceptible to parasites, and it could very well just be a coincidence. Like I said, just wondering if anyone else thinks the parasites could have been introduced in the frozen food. I have quite a bit of this food left and it was pretty expensive so I'm wondering if I should toss it.

 

[Humblefish]

Nothing is impossible, but freezing for at least 24 hours should kill any & all pathogens.

 

[ReefdUp]

No idea on cryptocaryon irritans resiliency to below-freezing temps, but I doubt that's the cause.

First, there's no way for a contaminated frozen food batch to create a tank pandemic in two days.

Second, you're only QTing your fish, not treating. So, chances are, the parasite is present.

Third, you didn't mention running fallow. So, chances are, the parasite is present.

I've only known of one case of frozen fish food introducing a parasite, and it was intestinal.

Root cause: the parasite is in your tank and has been.

 

[Hitman]

I wouldn’t think a parisite could live through the freezing process.

 

[DarkSky]

Like the others said, freezing would kill any potential parasites fairly fast. Lack of proper QT protocol is what did you in.

Make sure you've let your display be fishless for 72 days to completely eliminate any ich in the system. If you put your 30 day QT fish back into your display, there's a great chance chance they'll just get it again.

 

[Crabs McJones]

Agreed with above. Perhaps the process of feeding the frozen is some type of stressor to the fish. Do you do anything different from non frozen food feeding?

 

[Frogger]

However frozen food if not properly frozen or allowed to thaw and refreeze could spoil. Feeding bad food to fish could stress them and make the fish more susceptible to things like ich. Often ich lays dormant in your tank until there is a stress.

 

[theKoolAidMan]

Almost certainly not from the food. Either the Moorish Idol already had ich when you bought it or ich was already in your tank. My guess would be it was already in your tank from other fish you added in the past. The fish in your tank were healthy and their immune system was able to fight off ich attacks enough that they would likely often never show signs, making you think your tank was completely ich free. You added the Moorish Idol which stressed it and it wasn't able to defend against the ich attacking it in the tank and had a breakout.

It's also possible the Moorish Idol was already carrying ich but you couldn't see an obvious signs in the LFS. A fish can have ich but not be covered in all the obvious white dots. Additionally they will often still eat and behave light normal even when they do. I once had a clownfish which was absolutely covered in ich. Looked like someone rolled him in a bowl of sugar. He never stopped eating, never showed signs of distress, and eventually pulled though. At the same time, NONE of the other fish in the tank showed any symptoms at all and were spot free, however if I had taken one of those "healthy" ones and put them in a new tank, that new tank would almost certainly how have some level of the parasite present from the fish I transferred.

 

[Jack22]

Thanks for the help everyone.

I forgot to mention that I went fallow on my display tank for 80 days so i should be good in the DT. I’ve QT several fish since then and not had any issue. I figured it was just the type of fish that may have brought it in. Just wanted to try to be sure.

 

[ReefdUp]

Quarantine is NOT treatment. Just because you don't notice any issues doesn't mean the parasites aren't present. If you want a 100% ich-free solution, you'd have to go fallow and then actually treat every single fish.

 

[jefra]

I agree it's unlikely anything was introduced through frozen food, but possible. Some ciliates (which Cryptocaryon irritans is a species of) produce cysts that can survive freezing even in liquid nitrogen.

 

[Jack22]

Thanks everyone. Sounds like it’s not the food, which is great cause I don’t have to toss a whole package of food.

Just finishing a 2 week treatment on the newest fish in QT. Everyone looks good so far. Looking forward to finally getting some new fish in the tank.