beware of whiskered fish and sandstone decorations [i have removed mine now] i had a albino cory who lost his whiskas,couldn't find any other sign of illness, but after a while when moving the sandstone rock which was beautifully carved so that the fish could swim thro it, i noticed it had become quite rough .... i then decided that my cory had become over zealous with tha algea and had worn away his whiskas.the carved 'holes' had also become bigger ,so beautiful to us it may be but i'm not so sure for the fishes pebbles