Bad nutrient?

[Catfish]

I remember a post on here a while back. I think it was on the skeeter pee section. Someone blamed a bad batch on bad yeast nutrient. I just looked at what kind I use and it's Crosby and Baker. Unfortunately I think that's what the person said they used also. Have any of you had a bad experience with a certain brand or Nutrient, Energizer, Tannin, etc?

 

[Wade E]

Unless its all clumped together I cant see how anyone would determine if its bad or not.