Well post 1300 YEEEE HAWWWW
ok enough with that .
On my 280 i had it really bad, had to take it completely apart and scrub the rock and clean in newer sea water.
Then put it all in the newer tank the 75 gal and it came back,
Then how i got rid of mine was dried out all my rock , Not a good thing to do.
emerald will work, but it will be a hit or a miss.
good luck