Leather Affecting Zoas

[masimake]

I have a small colony of zoas that seem to be slowly fading away. All other zoas in the tank are doing great. I was wondering if the the Devils hand leather right next to the colony could be affecting their growth.

 

[650-IS350]

Could be chemical warfare by I could be wrong.

What's your parameters flow lighting etc?

 

[masimake]

All parameters great. Lighting is t-5 and all other animals are thriving. Might just try and move either the leather or the zoas