JL aquatics semi-cured live rock

[Coasting]

There will always be some die off no matter who or where you buy from. Its just what happens when you remove rock from water and transport then change to different water.
You will still need to allow the rock to cycle properly.
Ive seen a few members only use rock from stores or order direct and not have it even touch store water to avoid pests lile aiptasia thats so easy to get from member tanks. Maybe one of them will post.