Really, because I was just thinking about this issue and trying to decide if I should do the macroalgae or a remote dsb in a bucket.
I'm not claiming it can't work. IMO, it did work well before I added a lot of macroalgae. Lots of bubbles if I poke the sand and such. Now I think the macroalgae gets it and not the sand bed. No more bubbles to be seen, even if I poke into the sand. So it is an idling bed waiting for nutrients that never come.
