ID? Pretty bad pics.

[ianck]

New tank and examining LR and I find this round purple thing on the rock. Nothing else on the tank has this shape or color. It is slightly raised and a little grey in the center. Size is about the size of a pencil eraser.

Sorry for the bad pics.

 

[Tahoe61]

Try looking at Foraminiferans, but that is just a wild guess. Water is too cloudy and not the best of images as you already know.