Fish Dead, Corals affected, no obvious reason why...water quality or toxin release?

[Sk8r]

RUnning carbon, Purigen and PolyFilter would cover many bases, just in case.

 

[bertoni]

I'd run Cuprisorb rather than a PolyFilter as a regular filtration mechanism. The PolyFilter will leach some copper into the water in most systems, although the amount will be small.

 

[Sk8r]

Thanks for the input, Bertoni.