Scopas Tang Troubles

[colby90]

I have had this fish for at least 6 months. I got it when it was small it has grown but not too bis yet. It is in a tank with 2 clowns, 3 anemones, brittle star and hermits. It has been fine for as long as i have had it, 2 days ago i noticed a small white dot on its tail, i have done a water change and today when the lights kicked on the dot had turned into more of a section of his tail and bottom fin has lost its purple color and turned white. The fin is not tattered or torn it is still the the same shape with no missing pieces. When i feed he eats just the same, he swims around and is lively. He does not hide or sit on the bottom, no labored breathing. Could this be fin rot or something else? I will admit i have been working a lot lately and have missed a water change, could this be a result of that possibly? Neither of the clowns have any dots spots or patches only the tang...

Thanks,
Colby

[leebca]

Colby,

Tangs are very susceptible to water quality. It does need to be kept high. Tangs are also extra sensitive to stressor other fishes take in stride. Tangs will change colors and shades with different attitudes and when under stress. So, you first want to be sure this is just not one of those situations where the color change isn't because the fish is frightened, upset, or otherwise being stressed.

There are other stressors besides water quality (which BTW you haven't provided much info about) which include, space (you don't say the size of your tank nor the exact size of this fish); tank mates (those fish you've listed be of little problem IF there's enough space, however hermits are not a good addition to a fish tank since they can and do attack fishes sometimes); and nutrition (you don't list what you're feeding, how much you feed, how often you feed, etc.).

When Tangs do get into one of the above situations, their health slowly declines. They easily get infections (like fin rot) or succumb to slow starvation (from the incorrect diet).

So without a photo and without more info, there isn't much I can help you with other than to give you the above information. Your description doesn't fit fin rot and since it is only the tail, it doesn't quite fit the general color and hue changes Tangs are known for. This primarily leaves an infection developing or a reaction to a water quality matter.