Whats going on?! Bleaching??!

[Mockmo]

So ive had these candy canes for about 4 months now and the purple outer area is starting to turn white. THis happend before and i thought it was just too intense lighting so i put them at the bottom of my 75 gallon tank, and they began to get their original color, and this was about 2 or 3 months ago. Now they are getting pretty white, you can see in the pics. Any help on what to do would help! thanks!

Before:
<a href="http://s82.photobucket.com/albums/j269/skyline8900/?action=view&current=aac1c6e0.jpg" target="_blank"><img src="http://i82.photobucket.com/albums/j269/skyline8900/aac1c6e0.jpg" border="0" alt="Uploaded from the Photobucket iPhone App"></a>

After:
<a href="http://s82.photobucket.com/albums/j269/skyline8900/?action=view&current=49dc8952.jpg" target="_blank"><img src="http://i82.photobucket.com/albums/j269/skyline8900/49dc8952.jpg" border="0" alt="Uploaded from the Photobucket iPhone App"></a>

 

[y0ung0ne]

What is your water chemistry? need more details to help like lighting and changes? water changes to help with this.

 

[Mockmo]

i do 10% every 2 weeks my lighting is 4 bulb t-5s, parameters are as follows:

Calcium 380-400 ppm
Carbonate hardness 125.3 ppm
Phosphate .25
Nitrate 20
pH 8
Nitrite 0
Ammonia 0
Salinity 1.025