The color isn't a varient, but rather a sign of stress levels. Generally the lighter the color the more stressed they are. Of course some are going to have a naturally lighter coloration as well.
White King Tiger
- Thread starter slowlyburn
- Start date
This fish has been this color since it came in to the store 3 weeks ago... all of the others were yellow.
Coloration has a great deal to do with the strain of fish (some, such as the belo-monte numbers, are quite nearly all white in unmarked areas), diet, and as stated, stress. It should be noted that a lot of "L-66" come in looking white and are henceforth sold for large sums of money, and eventually turn a golden color; perhaps due to ca-tine (insert number) found in many commercial fish foods.
I'm very happy with this pleco. It is by far the most active one in the tank. On planet catfish they show white adults. I guess it doesn't matter right now. Only time will tell if the white will stay...
They are about 35.00 to 45.00 common at lfs around here. 
So I would say they are getting more common
So I would say they are getting more common 