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10.2.2.1. Witte stip in meer detail

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Auteur : David Bogert

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7 minuten
Difficulty : Level 8

Excerpt :

What is some of the science behind the most common fish disease, a protozoan called "Ich"?

MYTHBUSTER: ALLE goed uitgevoerde wetenschappelijke studies door onderzoekers over hitte en witte stip hebben ontdekt dat hitte totaal niet effectief is bij de behandeling van witte stip!

Merk op dat er twee andere ziekten zijn die op witte stip lijken (tetrahymena bij levendbarende vissen en epistylis bij andere vissen). Let dus op dat je witte stip hebt.

Openbare aquaria gebruiken formaline/malachietgroen (Ich-X, Rid-Ich Plus, Blue Planet White Spot Remedy, AquaCare Anti-Fungus & White Spot en Mardel QuickCure) om witte stip bij zoetwatervissen te behandelen, net als University Research Centers, Cory of Aquarium Co-op en Joey.

 Opmerking:

  • NOOIT het filter uitschakelen, het filter verwijderen, het filtermedium vervangen of het filtermedium reinigen. Als de koolstof langer dan twee weken in het aquarium heeft gezeten, verwijder deze dan NIET (in tegenstelling tot sommige aanwijzingen). Dit is erg belangrijk.
  • Verplaats de vissen NIET naar een quarantainebak (in tegenstelling tot sommige aanwijzingen).
  • Formaline en malachietgroen zijn beide giftig in doseringen die groot genoeg zijn, dus volg zorgvuldig de doseringsinstructies op de medicatiefles.
  • Als men de temperatuur verhoogt met formaline/malachietgroen kan de medicatie enigszins giftig worden.
  • Cory en anderen hebben zonder enig probleem duizenden "schubloze" vissen behandeld met volledige sterkte formaline medicatie
  • Formaline/malachietgroen is bij de juiste dosering niet giftig voor slakken of garnalen.
  • Bij 24 graden moeten formaline en malachietgroen elke dag worden toegevoegd om effectief te zijn.
  • Volg de aanwijzingen op de medicatie met betrekking tot waterverversingen.
Witte stip
Witte stip

De baanbrekende studie over witte stip behandelingen (Tieman en Goodwin, 2001) vond dat zout (0,25%) en warmte geen effect hadden op witte stip. Andere studies zeggen dat 0,5% tot 1% zout de mortaliteit door witte stip kan verminderen, maar niet zo effectief is als medicatie. UV-sterilisatoren, zelfs bij lage wattages, kunnen enorm helpen om witte stip uit het aquarium te verwijderen.

Established filters have thousands of little carnivorous critters in them which eat the infectious ich stage (the “theront”), so the filter is very important. The net result of this filter “medication” is that if you have a long-established aquarium filter with plenty of brown “gunk” in it, it is perfectly OK to do absolutely nothing for the ich. It will simply go away on its own in a week or two.

Because ich will go away in an established aquarium, there are at least 55 “treatments” currently “absolutely guaranteed” to stop ich.  There is an old saying in science: “correlation does not imply causation”. ANY treatment of ich in a tank with an established filter will work. The ashes from the cremation of a dead squirrel will work to remove ich in a tank with an established filter

Ich Biology

Ich is short for Ichthyophthirius multifiliis, a relatively large single cell, ciliated protozoan, closely related to epistylis, tetrahymena, and spironucleus (“hexamita”). It manifests itself as small white dots on the fish, like salt sprinkles. There can be tens or hundreds of dots on a severely infected fish.

Vier vissen met witte stip
Vier vissen met witte stip

The life cycle of freshwater ich has three distinct life stages:

  • the single trophont
    • A roughly 2-millimeter diameter “white spot” in a case on the skin or gills of the fish
    • Feeds on fish mucus and cells
    • Lasts 2 to 5 days at 780 F
    • Drops off as a single cell
    • Resistant to medicines other than malachite green and methylene blue.
  • the single tomont
    • A single cell in a case which attaches itself to plants, decoration, sand or gravel with sticky mucus
    • Lasts 1 to 2 days at 780 F
    • Multiplies into about 500 to 1,000 cells inside the case
    • Case ruptures, freeing the multiplied cells
    • Resistant to medicines other than malachite green and methylene blue.
  • the 500 to 1,000 theronts
    • A tiny ciliated cell (50 to 100 microns in diameter) that is free swimming and infectious
    • Lives 2 to 3 days at 780 F
    • Can be attacked easily by medications
    • Finds a fish and attaches itself, growing into a white spot the size of a grain of salt
    • Killed by formalin/malachite green or copper

So at 780 F the life cycle of ich is 5 to 10 days, with 7 days being a good average.

Witte stip
Witte stip

Fatality of Ich

Ich is simply rarely fatal in healthy warm water aquarium fish.  The ich organism is removed by established filters in the aquarium quite easily after the initial infestation. This is why those who get high mortality with ich are invariably newcomers with a newly set up filter which doesn’t yet have the “brown gunk” that literally “eats” the ich organisms.

The members of about ten Facebook aquarium groups were asked: “Of the cases of ich that YOU have had in YOUR aquariums, how many fish died?”. There were about 70 replies. Three of the replies had fish which died. All these three instances were where new fish were added to new aquarium. All the rest of the replies had no fish deaths, including one keeper with 200 aquariums for 30 years and one who had many aquariums for fifty years. This is very revealing. Ich is just rarely fatal in the established home aquarium.

There are is an exception to the “rarely fatal” conclusion. Sometimes fish get ich on the gills which allows bacteria to invade the gills. This results in “bacterial gill disease”. If one sees a few spots of ich, bacteria can be invading the gills and cause “gill disease” concurrently with the ich.

With gill disease the fish “pants” and hangs motionless in one place. The gills become bright crimson red and inflamed. There can be spots of red at the base of the pectoral fins and a thin papery look is found on the gill plate due to mucus. This is a serious disease, much more serious than the ich that might have initiated it. It needs treatment with a broad-spectrum antibiotic.

Witte stip
Witte stip

There are also possibly some other organisms which are very much like ich in appearance but are close cousins of the ich organism. These ich cousins seem to have a higher mortality and are reportedly becoming somewhat common in Europe. I say “reportedly” as I can find no really good information on it.

There are also two organisms not closely related to ich which can look just like ich. If one has the white spots typical of ich and livebearer fish are rapidly dying, almost always the culprit is another organism called Tetrahymena. Tetrahymena is almost always is indicative of water with a high bacterial count. Added filtration is the only good solution. Tetrahymena is especially prevalent among guppies and other livebearers.

Fish other than livebearers get a bacterial disease called “columnaris” which can be rapidly fatal. This bacterial disease is often accompanied by an organism called “epistylis”. Epistylis looks much like ich and is often confused with it. Easily 50% of the cases of ich seen on social media are actually columnaris with secondary epistylis.

Witte stip
Witte stip

Ich Dormancy

One common controversy is whether or not ich can survive without fish. Most social media “experts” say that ich cannot survive without fish for more than two to four weeks. But there is absolutely no scientific research I could find that supports this conclusion. And there is one well done study which disputes this “expert” opinion.

On the American Aquarium Products website there is a well done study of ich done with replicates and controls. This test showed the ich organism APPARENTLY does lie dormant in a fishless aquarium for a long period of time (several months). These dormant ich organisms can break out in new aquarium fish if the filter is removed or cleaned very well along with other stressors being done.

We emphasis “apparently” as there is another possible explanation, namely that the “ich free” fish actually had ich only on their gills and only got it over all their bodies when they were stressed. Most scientists feel that ich cannot survive for more that a week or two without a fish host. Personally I have never had a case of ich break out in a tank where no new fish have been added. NEVER. Which is one of the reasons quarantine for four weeks minimum is so important to me. I have had cases of ich in quarantine aquariums, especially if the fish are from big box stores.

Witte stip
Witte stip

Witte stip in meer detail

Ich is the most common fish disease and warrants a more in-depth discussion. The following chapters are devoted to this common fish disease:

10.2.2.2. Immuniteit van vissen voor witte stip

10.2.2.3. Witte stip medicijnen

10.2.2.4. Witte stip medicijnen in meer detail

10.2.2.5. Ineffectieve witte stip medicijnen

10.2.2.6. Filtering gebruiken om witte stip te verwijderen

10.2.2.7. Witte stip behandelen met warmte