I dose fairly high with Fe (EI dosing with 3/8 t. of CSM+B plus 1/8 t. Chelated Fe three times a week in my 72 gal) and have no hair or thread algae at all.
"Hair, Thread, Fuzz, etc. Algae: Nothing to do with excess iron as commonly thought."
According to this very informative website on Algae:
http://www.theplantedtank.co.uk/algae.htm