Need Ich Advice

Mghanayem

New member
Hello all, i have a few questions. First, I have a tank with a snowflake eel and a lawnmower blenny, all other fish have been killed off by the ich. Neither of these have any signs showing.

1. If I leave the tank alone for a 3 months with those fish in it, will the ich eventually die off? or keep reproducing?

2. Can snails get ich?

3. Can hermit crabs get ich?

4. are eel immune to ich?

5. are lawnmower blennys immune to ich?

6. Do I need to pull everything including snails, coral and hermit crabs (as well as eel and blenny) and leave it alone for a while to get rid of ich?

7. How long should I keep my tank empty if I get rid of the fish to ensure that the ich is gone?
 
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1. No with fish or the eel present the ich life cycle will continue

2. They can host the cyst stage of ich

3. See 2

4. No not immune but are thought to host it only in their gills

5. No fish is immune to ich, though some never seem to show signs of it and others can develop temporary immunity.

6. You need to pull the fish and eel and treat separately. Leave the DT fishless for 72 days, longer than that would be better.

7. 72 days minimum
 
Great, Thank you!

So after pulling the eel and blenny, I can keep the snails, crabs and coral frags in there?

I intend to leave it alone for weeks, cycle the tank again and replace the media, then start from scratch.
 
...
5. No fish is immune to ich, though some never seem to show signs of it and others can develop temporary immunity.
...

Not naturally immune, but all fish can acquire immunity after surviving an ich infection. The level of immunity can vary from partial to full and may be maintained as long as ich is present. Without ich present the immunity may be lost after a while (~6 months).
 
Not naturally immune, but all fish can acquire immunity after surviving an ich infection. The level of immunity can vary from partial to full and may be maintained as long as ich is present. Without ich present the immunity may be lost after a while (~6 months).

For a given strain.
 
For a given strain.

I don't think that has yet been conclusively proven. All known C. irritans strains are genetically close enough to be fought off by the same immunity mechanism.
The tests Burgess did were just with one isolate and I. multifiliis as comparison with a "closely related species". Based on that he concluded that immunity might be strain specific.
Though latest DNA research has shown that C. irritans and I. multifiliis are not at all closely related but rather the results of converged evolution.

In my experience, some fish never show any symptoms, regardless how bad ich rages in their tank and where the strain comes from. I just had such a case and it was for sure a newly introduced strain (from a Bali shipment).
3 regal angels got covered in it while 2 marine bettas and 2 percula didn't show the slightest symptoms.
 
I need to see if I can find it when I get home.

There has been a lot of work done on the immunity research in recent years and acquired immunity against protozoan parasites is much more common with fish than previously thought. One study I recently discovered found that the fish's immune system actually kills the attacking parasites with antibiotic like substances. So it is not just that immune fish wart off attacking parasites but actually actively destroy them.
 
This is the article that shows the rRNA similarities of several analyzed C. irritans strains:

Characterization of Cryptocaryon sp. isolated from marine fish in THAILAND and in vitro treatment

Only two strains from Taiwan (Penghu, Kaoshiung) are a bit further off. Those are the low salinity strains.

Characterization of Cryptocaryon irritans, a parasite isolated from marine fishes in Taiwan

Thanks, great articles. I found the scanning electron micrographs in the first article fascinating. I didn't see anything about immune response in either article, though.
 
So I can pull the fish and leave the snails, hermits and coral frags in there.

I intend to trade in the eel as he's now 30 inches long and thicker than a cigar and the blenny as well.

If I pull just the fish and leave it for a few months before restocking, will that work so that the new fish will not get the disease?

Will it die off by then?

Thanks in advance!
 
So I can pull the fish and leave the snails, hermits and coral frags in there.

I intend to trade in the eel as he's now 30 inches long and thicker than a cigar and the blenny as well.

If I pull just the fish and leave it for a few months before restocking, will that work so that the new fish will not get the disease?

Will it die off by then?

Thanks in advance!

72 days without fish and the DT will be ich free. Now if you don't QT and actively treat or know what to look for as far as disease indicators then QT will be mostly useless. Just assume that all fish you get have disease because truth be told, they probably do
 
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