ICH

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How long have you had it in the tank?

For some reasons Hippos are ich magnets.

Become familiar with the life cycle of ich

• Tomont Stage: The parasite forms a membrane and attaches itself to the substrate in the tank whether it is sand, rock, and/or glass. The parasite then reproduces and proceeds to the next stage. The time that this stage in the life cycle can last a few days to almost a month depending on the temperature of the water. The warmer accepted end of temperature of a saltwater aquarium would increase reproduction rate and vice-versa, in terms of the colder accepted temperature.
• Theront Stage: The parasite then hatches and begins to swim through the water column in search of fish to attach to. It only has a limited time of up to 72 hours to find a host or else perish. Each hatched parasite can attach to the same fish, further stressing the fish.
• Trophont Stage: Assuming the parasite finds a suitable host it grows large enough to be considered an adult specimen. This part of the cycle usually lasts up to a week. The white spots are 0.5-2.0 mm in size with infection origination in pectoral fins before spreading to the rest of the fish.
• Trophont Free Swimming Stage: The parasite drops off the fish after it has grown and searches for an ideal surface to begin the tomont/reproductive stage again. The speed of attachment can last from an hour to eighteen hours.