The Puffer Forum

This is just for general knowledge and not an emergency. I thought Ich had a 3 stage development:
1)cyst
2) free swimming and looking for a host
3) found the host and it is a parasite dropping eggs (#1) all over the place.

This is similar to flea development.
Another person mentioned that there is a 4th stage:

As long as the trophont stage of the parasite in incysted in the cuticle of the fish, no meds will affect. When the tomont stage leaves the fish to swim to the bottom then meds will affect it. Once, on the bottom the chems will no longer affect it. When the tomites are release back into the water column to find a host then the chems will affect it again. Vacuming the gravel will help remove some of the tomites

That is a 4 stage development... and for years I was under the impression it was 3 stage. Can anyone confirm / deny or enlighten?

Isn't it the same as #3?

that is 3 stages ??!?

Yep, just like fleas.

I've heard it both ways but it is confusing. There are three maturation stages the parasite goes through in life but it's actual infection cycle (for lack of a better term) consists of four phases. There is the trophozoite stage where it attaches to the fish, lives off the fish and becomes encapsulated. As the trophozoite matures, it becomes known as a hard trophont and leaves the cyst and sinks to the bottom of the aquarium. On the bottom the trophant reproduces by splitting within itself and then bursting and releasing tomites. The tomites swim to find a host and start the cycle all over.

The infestation cycle is considered four phases: living on the host, falling from the host, reproducing on the bottom, and free swimming and seeking a new host.

+1 to Dadof4's comments. That is to me clear and accurate.

To me, J-P's first post is muddled, both his description and the quote. Both are confusing and misleading - actually in error.

Thank for the replies.

Sorry it sounded confusing. That is because I was confused. I am trying to do some online research on it now and learn as much as I can about it.

Things which are important to know about FW Ich:

1. It is a temperate water parasite. Wild caught tropicals have no immunity.

2. It is a gill parasite primarily, preferring the gill epithelium above all other sites for infection. This means that you may have Ich in a tank with no visible lesions. Visible somatic (body and fin) lesions imply that the gills are already heavily infested.

3. Ich has no dormant form. The parasite's life cycle requires approximately 3 days, but only in the true tropical temperature range of mid to upper 70sF. Above 80F the parasite does not do well. Lower temperatures greatly extend the length of the life cycle.

4. The only form which can be treated in tanks by medication is the free-swimming infectious stage, which must find a host within hours or it will die.

5. Chronic low-grade infections are possible and are not rare.

6. Post-infection and chronically infected fish have antibodies against the parasite. But stress of any sort can reduce the fish's immune function enough to make the antibodies ineffective. Water quality is very important in maintaining immune levels, ditto for freedom from stress by other fish. Immunity against the parasite does fade with time in other than chronically infected tanks.

7. Natural immunity varies widely with the fish species and the age of the fish.

8. Warmer water holds less oxygen. Uninfected fish may well be fine at temperatures which infected fish cannot survive due to the reduction in gill function. Recovered fish will eventually repair or replace damaged gill filaments, but some degree of scarring is apparently permanent, with some degree of gill function reduction commonly being permanent.

There may be more, but that is all I can remember at the moment...

HTH

HTH

Thank you for the info. I had found a few articles on them yesterday. This does help simplify the things.

http://www.reefs.org/library/aquarium_n ... 197_1.html

http://www.maine.gov/ifw/fishing/health/vol3issue4.htm

http://www.freshwaterlife.org/imagearch ... temId=3930