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How did Ich get in the tank? Ich has often been attributed to poor water quality, and this is true. However, water quality alone is not the only cause, since it is a parasite it had to come from somewhere. Ich often enters the aquarium on plants, driftwood, or even newly added fish. Poor water quality, however, does create an environment that is much more conducive to the growth of ich. For this reason it is important to keep your water quality high regardless of what fish you have.
A marine form of the disease also exists however treatment is different. For obvious reasons the salt method does not work. Many of the medications that exist for treatment of marine ich are copper based and thus are unable to be used in a system where invertebrates are present. If nor inverts are present then these meds can be added directly to the tank. If inverts are present then a non-copper based product must be used for the tank.
Ich prevention Prevention is fairly simple. Keep you tank clean with regular water changes and gravel vacuuming, and examine new fish carefully. To prevent Ich from getting into your large system a smaller quarantine tank should be established and new fish should be held there for 2 weeks to allow any possible problems to come out.
Sources:
Fish disease: White spot* (Ich), protozoan parasite.
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