How to Treat Tropical Fish with White Spot Disease (Ich)
Bartelme, Terry D. 2001. "Treating Saltwater Ich Without Medication" Tropical Fish Hobbyist, January 2001.
Marine Ich, Crypt, or Marine White Spot Disease is one of the most common maladies experienced in the marine aquarium, with the other being Marine Velvet. It can grow in environments with excessive stress, poor water quality and fluctuations in water temperature. It can also come into the aquarium on a new fish that is a carrier. This protozoa has four phases to its life, lasting up to 38 days depending on the temperature of the environment. This parasite affects marine and brackish fish. Aquarists are most familiar with the stage where the protozoa is infesting the host, with small white spots on the fish's body and fins. Unfortunately this visual clue is also the reason for difficulty in eradicating marine ich. Once the parasite has left the host's body many aquarists believe their fish is cured and the problem is solved and so they cease treatment, only to have another larger reoccurrence.
Leaving the tank devoid of fishes for 28 days should do the trick for the tank. Depending on the fishes, I'd treat the whole lot in an established aquarium, not a fish bowl, for the suggested duration. My favorite Ich meds are Maracide (made by Mardel) and Epsom salt (3-5 ppt for 21 days). Your palnts will not like either treatment, but if they stay in your viv for 28 days with no fish, it should be safe, provided the water temp is 70F or higher.
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I once purchased some corydoras catfish for one of my aquariums from a pet store that didn'tpractice the best fishkeeping methods. Unfortunately, the fish had ich. I knew it was a possibilitywhen I bought them, but I was planning on keeping them in their own tank with no other fishand so I thought that I could treat them. In fact, I thought I was "saving them" from the fate they would most likely encounter at the pet store. Many hobbyists are fooled into believing they have cured their fish of the parasites, only to find Ich present again on fish a few weeks later; a reason why following through with a full treatment protocol is so important. Don't make this mistake and be lulled into a false sense of security. The parasites may be in a stage where they are merely regrouping and multiplying for their "next offensive." In the wild, this sort of massive reproductive phase ensures that a few will find a suitable host to continue on the cycle. In the close confines of our aquariums, though, it means comparatively massive infection rates.I began treating them with a formulin based medicine. It didn't work and two of the fish died (therewere 5 total). I did a partial water change and then used a copper sulfate solution and the ichproblem cleared right up. In fact, I've used copper sulfate to treat ich many times over the years and it generally works forme. I use the Mardel brand. The other brands of copper sulfate (if there are any) are probably just asgood for treating ich, but I've always had good luck in using the Mardel products to treat avariety of fish diseases. With the Mardel products, in most cases, you don't even have to removethe activated charcoal to treat your fish. This is usually true for all of their products.Prevention: saltwater ich parasites are commonly found in nature, and we can safely assume that many normal, healthy fish are carrying a few of these parasites when collected. Since no treatment has been found that can kill ich while embedded in the fish, we must wait for all of the parasites to fall off on their own before we can consider the fish to be ich-free. In the meantime, of course, effective medication must be used to prevent re-infection. Ideally, each hobbyist should have a medicated quarantine tank, to isolate and treat each new specimen for at least two weeks before addition to the main aquarium. Another option is to purchase only specimens which have been kept in properly medicated tanks at least two weeks at your dealer (we medicate all our fish-only tanks full time and we date our fish labels to help you with this). Saltwater invertebrates are suspected of being carriers of ich, and since most effective ich treatments also kill invertebrates (their cell structures are quite similar), they cannot be guaranteed ich-free when purchased.