sounds like there is another problem, here,
my blenny does not do that, and wiht your system
if i remember right, lr, a dsb and a skimmer, you should not be seing it for long, if it were, and they should look more stringy, and not terd like
couldn't be little clumps of algae, could it??
or excess food(which should dissapate soon too)
any chance of a better description??, than terds
HTh