The TGC will eat some of the algae then, given your situation. They will also be rooting around in the pond bottom to see what they can find to eat if there are no plants. Having some plants will help with the FA problem, so getting plants established will be impossible if the TGC are in there. Find out from Jones the % of male/female Tilapia.that they sell.

www.hoosierpondpros.com

[Linked Image from lh6.ggpht.com]
http://www.pondboss.com/subscribe.asp?c=4
3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).