Algea eater fish

Question
I have had this placemoto algae eater (however you spell it) since setting up my tank around 1992.  It is now approx 7 to 8 inches long.  Just noticed the fish is turning white, or has something white on it.  Appears that a white coating is even on the eyeball.  Any idea what is causing this?  There are approx 5 small bali sharks I have in the 25 gallon tank with it; for about six months now.  They look healthy.  Only thing new in the tank, is I added 3 live plants, to replace the plastic ones, I have had in the tank for about 6 years.

Answer
Hi Art;

How often do you make water changes and vacuum the gravel?
Plecostamus can develop infections from gravel that hasn't been kept very clean. Overfeeding is the cause. We all do it from time to time, we just have to remember to clean up after ourselves when we do. To get things in good shape again, vacuum the gravel twice a week while removing 25% of the water. Once you get no crud coming up while vacuuming, cut back to vacuuming once a week while removing 25% of the water. Cut back on feeding too. There should be no food leftover anywhere in the tank after 5 to 10 minutes. If there is, feed less the next time and keep doing this daily until the right amount of food is going in at every feeding. Once a day is enough.

If he seems lethargic he may also need medication, but usually cleaning and water changes is enough. If he is still sick after cleaning for a few days, check your local fish store for a medication that has packaging describing the symptoms your fish has. Use it according to the directions.

Something you will have to consider soon is getting a large tank of 55 gallons and then another in a year or so of 100 to 150 gallons for the balas. Bala sharks can't live in a 25 gallon for more than a few months. They get a foot long.

Followups welcome

At Your Service;
Chris Robbins

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