bimmer01..the frag I got from you looked like those too when they were on the bottom, but when I moved them up higher the discs turned solid blue .....
Just need to add..IF they are Tubs or any other blue colored zoa..the blue ones are not usually inclined to like a lot of lighting. Sometimes they melt away when subjected to strong lighting. If you are going to move them up, do so slowly and only about 2 inches at a move. (I'd also suggest you leave them at each level for a couple of weeks before moving them further..they can be tempermental at times )
If they start to stress, move 'em back down.