How to detect if Ich is present?

[3FordFamily]

Oftentimes the parasite is undetectable. For each spot you see, there are hundreds others in the gills and elsewhere that you cannot see. Just because you don't see the parasite in no way shape or form on any planet means that it doesn't exist in your system. I have one system (my 180 reef) that no matter what stress is brought on, the inhabitants NEVER show signs of ich. It does, remain in the tank. New additions are affected, generally temporarily.

 

[Deinonych]

Again, if the parasite is never introduced to the aquarium, fish will not be affected by it. Fact.

 

[Clowny88]

Oftentimes the parasite is undetectable. For each spot you see, there are hundreds others in the gills and elsewhere that you cannot see. Just because you don't see the parasite in no way shape or form on any planet means that it doesn't exist in your system.

This is exactly why, when I QT, I wonder why I'm wasting my time looking for signs of ich.

 

[snorvich]

This is exactly why, when I QT, I wonder why I'm wasting my time looking for signs of ich.

Well, ich is easily removed with tank transfer, when you quarantine you are accomplishing several things:

+ Providing the fish with a chance to develop a feeding process with no competition
+ Isolating any possible parasite (such as brook, uronema, velvet, septicemia) from wiping out your display tank. Ich won't in the short run, the other ones will.

 

[ThRoewer]

Oftentimes the parasite is undetectable. For each spot you see, there are hundreds others in the gills and elsewhere that you cannot see. ...

If a fish has hundreds of parasites in its gills you will see it on its behavior.

... Just because you don't see the parasite in no way shape or form on any planet means that it doesn't exist in your system. I have one system (my 180 reef) that no matter what stress is brought on, the inhabitants NEVER show signs of ich. It does, remain in the tank. New additions are affected, generally temporarily.

I disagree. I'm fairly confident that if all your fish are resistant enough that you can't see it, it will eventually die out because the fish's immune system will fight the parasite even in the gills enough so that it can't feed enough to get to full strength.

And in a reef tank the off-fish stages of Cryptocaryon and especially the rather large protomont stage have plenty of enemies (hydroid polyps, corals, sponges, feather worms, clams ...) so not everyone will be able to encyst and reproduce. And those that manage to encyst may fall victim to predation (or accidental ingestion) by copepods, snails, worms and whatever else lives in or on your gravel and rocks. And finally the theronts not only have to survive the same predators but also have to find the Achilles heel of the resistant fish (the gills) to start another cycle.

It's a numbers game and I think in a reef tank with few resistant fish the odds are stacked against the parasite.

Keep in mind that almost all the research has been done with aqua farming in mind (they are the ones who have the biggest interest in eradicating it in their systems and the money to pay for the research) and usually under conditions that rather resemble how fish are kept there (= bare tanks and high fish density) than a reef tank with relatively few fish and plenty of invertebrates.

Now, can you be sure if it is there or not? In most cases probably not.
But if your fish are stressed enough to temporarily have their immune systems weakened you will see Ich on at least some. If even then nothing shows up even for a short time you likely don't have Ich in your system.

And to be sure it is not there you need to follow a vigorous quarantine protocol.

 

[jbvdhp]

If a fish has hundreds of parasites in its gills you will see it on its behavior.







I disagree. I'm fairly confident that if all your fish are resistant enough that you can't see it, it will eventually die out because the fish's immune system will fight the parasite even in the gills enough so that it can't feed enough to get to full strength.



And in a reef tank the off-fish stages of Cryptocaryon and especially the rather large protomont stage have plenty of enemies (hydroid polyps, corals, sponges, feather worms, clams ...) so not everyone will be able to encyst and reproduce. And those that manage to encyst may fall victim to predation (or accidental ingestion) by copepods, snails, worms and whatever else lives in or on your gravel and rocks. And finally the theronts not only have to survive the same predators but also have to find the Achilles heel of the resistant fish (the gills) to start another cycle.



It's a numbers game and I think in a reef tank with few resistant fish the odds are stacked against the parasite.



Keep in mind that almost all the research has been done with aqua farming in mind (they are the ones who have the biggest interest in eradicating it in their systems and the money to pay for the research) and usually under conditions that rather resemble how fish are kept there (= bare tanks and high fish density) than a reef tank with relatively few fish and plenty of invertebrates.



Now, can you be sure if it is there or not? In most cases probably not.

But if your fish are stressed enough to temporarily have their immune systems weakened you will see Ich on at least some. If even then nothing shows up even for a short time you likely don't have Ich in your system.



And to be sure it is not there you need to follow a vigorous quarantine protocol.

Your thoughts echo what a member named Minh thinks regarding natural predation of the protozoan in the tank. He mentioned something along the lines of having other organisms in the substrate and water column that may just feed on whatever is in the tank. Big fish eat small fish, so to speak. Interesting food for thought.

 

[Clowny88]

Now, can you be sure if it is there or not? In most cases probably not.
But if your fish are stressed enough to temporarily have their immune systems weakened you will see Ich on at least some. If even then nothing shows up even for a short time you likely don't have Ich in your system.

And to be sure it is not there you need to follow a vigorous quarantine protocol.

This whole thread has been a very interesting read... Especially what you posted ThRoewer.

I had 2 clowns in a 45 gal, the female was beating on the male and he was clearly stressed after 6 weeks together. When he was really bad, he showed about 7-10 spots.

After he cleared up, I ditched her. I prepared a hospital tank. I've been delaying putting him in and treating with copper, just due to the fact that I don't want to stress him further for no reason.
That said, its been a couple weeks and he's doing well, despite getting a bit stressed when I changed up the rockscape completely.

I've been tempted to move him to the hospital tank and not treat with copper (unless symptoms pop up). But being the only fish in the tank, not showing symptoms and eating like a little piggy... I may subscribe to the "odds against the parasite theory". I don't plan to add another fish for a couple months any way while I build on some additions to my system. So this may be an interesting experiment.

Just seems like the odds against the parasite here... Barely showed in the beginning. And now have to survive a tank with minimal " host" life and more predator life to deal with instead.