There is differing research as to whether they will or won't affect BG and if they do, just how much... IMO, if you are going for a trophy BG pond, leave them out however I don't think there is that much competition.
As far as how much a truck load of TFS costs, you'd have to ask Greg. Send him a PM if he doesn't see this thread and run it by him. He can give you far better advice on that subject than I ever could whether is be price or the numbers needed.
