So unfortunately I lost two invertabrates over the weekend, one was a starfish and the other was a hitchhiker gorilla crab I had in the sump. I decided to test my copper with the Hanna Copper checker and it came back at 0.10. Is this high enough to cause damage\death to invertebrates? What should my next steps be? I'm planning on doing a 25% water change today. Not sure where the copper is coming from, I tested my RODI water and it was 0 for copper.