Corals dying

[Salreef]

I started my reef tank and it’s been 6 months old it began well until I noticed that my corals (hardy,easy care)started dying off .1 day I saw a piece of nail that rusted in my sump.Ive been noticing every time I buy a new coral it would die off .Do I need to empty my tank and start over again?please help

 

[Lasse]

I started my reef tank and it’s been 6 months old it began well until I noticed that my corals (hardy,easy care)started dying off .1 day I saw a piece of nail that rusted in my sump.Ive been noticing every time I buy a new coral it would die off .Do I need to empty my tank and start over again?please help

An ICP could help here. The rusted nail can be one reasons - but there is 100 of other things that also can be a reason for your observations. We need some more information like set up, nutrients levels, type of corals, other livestock, light intensity and so on. You are looking for a nail in a haystack . You found one -but can it be the one and only

Sincerely Lasse