I think it may have something to with moving your old sandbed. Did you vacuum it first? I think moving an existing sandbed can be very tricky, even potentially dangerous. Try searching this board for the recent DSB threads. As for what action to take, I would stop all chemical additions and start running some carbon, (as you're doing) along with a couple of 25% water changes over the next month or so. I would also start vacuuming off that algae that you describe. I'm assuming that it's a slime algae.
Also was the lighting changed much from the old tank to the new? The corals may be having a hard time adjusting to new light conditions.
Don't throw in the towel!
Mitch
Also was the lighting changed much from the old tank to the new? The corals may be having a hard time adjusting to new light conditions.
Don't throw in the towel!
Mitch