Eric, the disadvantages outweigh the advantages on this particular brand. Do a search (its hard to see and in red on the bottom right of this page) and you can see we discussed this topic recently.
Better a little stress away from main tank. Check out the posts mentioned above about GreenX it is not to highly thought of around this board. I have used it a few times and had no luck with it helping the fish. I really do not think much of that product to be brutaly honest with you.