I got the Keys rock too and then the same amount of Hirock.com base rock, within one months time it was getting corraline all over it (The base rock). It has been completely covered now, all of my rocks. My tank is one big sea of purple due to the rocks. Good rock. I think a lot of it has to do with the keys rocks being so purple. Also I gave my husband two rocks that I had from hirocks and had been established from all the other rock. He put it with all base rock where it is visable from all sides. They are COVERED in sponges (pink,purples,oranges, creams and yellow), corraline, spagetti worms...so many copeopods that the two small rocks FILLED his sand bed and rocks with them and I am sure there is more but it's what i noticed. It started out dead rock the keys rock seeded it, now it's seeding his. GOOD ROCK! I DO recommend some sort of dip though as there are a lot of fireworms in them and the big ones have a taste for soft corals.