Anyone feed fish Costco Nori?

[Aquattro]

Costco brand is, or one of their products anyway, treated with several ingredients, one of which usually kills your fish My guess is grapeseed oil.

The product has the ingredients listed, and is a smaller package, so should be identifiable.
I met a woman at the LFS that showed me the package after it killed all her fish. LFS had heard of it before.

Make sure there is nothing but dried nori in the package!