I may be wrong guys, but it sounds to me that you have been infected by the
insidious 'red bush algae'.
However, please do a google for the above and check photo's to confirm
diagnosis first.

I have just moved back from the front lines in a fight with this invader and
can tell you its a nightmare, it gets onto everything, rocks, bogwood,
heaters, filters, plants (esp roots) usually introduced by plants purchased
and introduced into your tank.
I had to go the bleach road as a solution. (19 parts water to 1 part bleach)

Once contemplated, genned up and acted upon you WILL win.

http://www.thekrib.com/Plants/Algae/bleach.html

Steve Page