Please explain the logic of ich and why tank inhabitants can get?

[ohiorn67]

If my tank does not have ich and I put another fish in ....say for example....a blue tang....who of course are known under stress to get this. Now I was under the impression that ich can attack a fish that is stressed at the moment that they are stressed. If the other fish are doing well and are not stressed, how is that many other inhabitants get the ich anyway if their immune system should be able to beat it. I don't mean to sound dumb, I have had my tank now one year and doing terrific. I really want to add another fish..have not done this for a very long time and have much bio room for one. I have been very nervous about not quarantining....I have yet to do this, for my fish I have had long before I had learned about quarantine tanks. I would like to know what to look for in a new fish before putting him into my established tank now? I know you all think quarantine, but so far I have been very lucky and have very healthy fish...I don't want to subject my others to a problem. Please help....

 

[squidd]

I have had my tank now one year and doing terrific

I have been very nervous about not quarantining..

so far I have been very lucky
That could end quick...
I don't want to subject my others to a problem
I think you answered your own question...

 

[pontius]

here's what I don't understand. if every fish in a community has successfully gone through hyposalinity, how can one of them get ich AGAIN just from being transferred to a new tank where there are no new fish and no ich?

 

[anthonynyc]

Originally Posted by Pontius
here's what I don't understand. if every fish in a community has successfully gone through hyposalinity, how can one of them get ich AGAIN just from being transferred to a new tank where there are no new fish and no ich?
They can't.
Anthony

 

[mystic7]

How about this scenario. You have a tank with one hardy fish in it, in this case a Niger Trigger. He had ich after a day or so in the tank, then beat it. There have been no signs of ich on him for 6 weeks. Ich need fish in order to survive, but they're not surviving on him. 2 weeks later I introduce two healthy fish purchased from someone whose tank they outgrew. Both were healthy (in fact the Hippo Tang is over 5") and the next day he shows up with a bad infestation of ich. Where did it come from? Aside from that, can a tank with one healthy fish in it for 8 weeks still have ich in it?

 

[anthonynyc]

Originally Posted by mystic7
How about this scenario. You have a tank with one hardy fish in it, in this case a Niger Trigger. He had ich after a day or so in the tank, then beat it. There have been no signs of ich on him for 6 weeks. Ich need fish in order to survive, but they're not surviving on him. 2 weeks later I introduce two healthy fish purchased from someone whose tank they outgrew. Both were healthy (in fact the Hippo Tang is over 5") and the next day he shows up with a bad infestation of ich. Where did it come from? Aside from that, can a tank with one healthy fish in it for 8 weeks still have ich in it?
OK here's what I think.
I think Ick was still in the tank and alive and well. Ick only attaches to the fish, the visible stage, for a certain amount of time. After that, they drop off and you cannot see them. I've read that triggers are pretty hardy fishes and were probably just waiting for another host.
My experience is that it's easy to miss. I thought I cleared all the ick in my tank until I turned the lights on in the middle of the night and saw my yellow tang covered. I went to sleep and sure enough, in the morning, he was ok.
From what I read somewhere, Ick actually are very smart. When they attach to the fish, they actually wait for the lights to go out and for the fish to sleep. That is when they drop off the fish and multiply knowing that the fish will usually return to the same spot to sleep and they can reattach to them.
That's my theory!!!
Now, if you said you left the tank EMPTY with no hosts for 6 weeks, then introduced the tang from a definitely non infected tank and it got ICK, I would not know what to say. We need more experienced people to respond to these posts.
Anthony

 

[beth]

Ich is a fish disease, though in remote cases, there is a possibility of contaminating a tank where there has been no ich by introducing LR, hard shelled animals, instruments, contaminated water, etc., into the ich-free tank.
Ich is not caused by stress. Ich is a parasite, not a stress disease. However, like all ailments, stress can exasperate an existing situation. I can stress a tang literally to death, but it would not necessarily result in ich if the fish did not have it to begin with.
In situations where ich is present, but not in strong forces, it is possible for the parasite to go undetected. That is why it is just a good idea to routinely give your fish the once over using a magnifying glass.

 

[beth]

Originally Posted by mystic7
Both were healthy (in fact the Hippo Tang is over 5") and the next day he shows up with a bad infestation of ich. Where did it come from? Aside from that, can a tank with one healthy fish in it for 8 weeks still have ich in it?
If you did not treat ich, then the trigger still had ich. And, the other fish may have had ich as well. It may not have been a life threatening disease, but it was there. Ich and fish live and coexist in the wild with few mortalities to fish. The parasite, by nature is not designed to kill off the host. It is the introduction of fish and parasite to the closed environment that makes this parasite potentially deadly. Most viable parasites are not designed to eliminate their livelihood.