We dont have a fuge, but in our DT we have a little patch of grape that dosent grow much and a fairly large red algae that looks similar to grape, but dosent grow like green grape. I'm assuming the big red is out competing the green, which is fine with me, I'd rather not have to harvest constantly. Anyway, the red stuff dosent grow rapidly, but does need trimmed from time to time. I love it and it gets me a discount at an LFS. I dont know how much "exporting" it does, but it isnt hurting. I've been contemplating starting a tank just to propigate the stuff. I'll try posting a pic, it may be old though. HTH.
Pic is from 4-10-04.