Am i crazy but it seems to me that there is a contamination problem. The OP mentioned fish dying, inverts dying and after 6months it looks ridiculously clean. Maybe copper leaching in somewhere, chlorine, ect. After 6 months of water and bacteria there will be some sort of growth.
The last two systems i set up where dry rock with bacteria and ammonia dosing doing a 4month cycle. After a month into the 2nd of just running water and bacteria with ammonia the rocks started to show color.
I believe there is more going on than needing to "dirty" the tank up.
The last two systems i set up where dry rock with bacteria and ammonia dosing doing a 4month cycle. After a month into the 2nd of just running water and bacteria with ammonia the rocks started to show color.
I believe there is more going on than needing to "dirty" the tank up.