[Delphinus]

Agreed Mitch, it has to go somewhere.

Despite its pitfalls macro algae harvest I think has some benefit. I think one key element is discipline: since sporulation presumably releases back a lot of what was previously absorbed, and since you cannot guarantee the prevention of sporulation, a better focus is mitigation of the damage this would cause (long winded way of saying, if you prune often, there's less of it at any moment to dump goo into the water column).

The other pitfall that is maybe not as easy to address is the issue of allelopathy. I've found, particularly with fast growing corals such as Acropora and other SPS, that the mere presence of some macroalgaes such as caulerpa, is enough to to negatively impact the growth of SPS.

In my case I've found proximity to be a key factor, so a remote macro harvest area should likely address the issue somewhat. I'm sure it's not a perfect solution and I'm guessing that although running carbon and perhaps other absorption resins may also aid in this aspect, I'm confident none of it is a true "silver bullet" solution.

It could just be however, that the positives outweigh the negatives (if properly managed). Although ... it's probably not the worst thing in the world if (at least some of) your SPS doesn't grow as fast as it could.

And of course there are other macros that may be less pervasive than caulerpa. Chaetomorpha seems promising to me, I've never heard of any real negatives with that one. The only thing I've found with Chaeto is that it seems to require quite bright light to grow effectively. Under moderate lighting conditions it is a slow grower (at least it has been in my systems, whereas in the past where I had it under HID it was a prolific grower).

Anyhow, those are my thoughts for the moment.