Keeping Your Wilds Separate?

Cross contamination through the air doesn't happen. What is much morel likely is infection through shared bottling buckets, racking canes and tubing. That said, I've used the same equipment for both sour and clean and haven't had a problem yet. <knock on wood> As typical, proper sanitation is key.

 

You can ferment them right next to each other unless you are fermenting as many barrels as say Russian River, which I am sure you are not.

I had a flanders right next to an IPA and both were fine.

 

I was a bit concerned about contamination when I brewed a beer last year with a combination of regular yeast and Brett. I contacted the Mad Fermentationist (Michael Tonsmeire) and asked him about the potential for contamination. He recommended that I just sanitize things (bucket, racking cane, etc.) as I normally do after using my equipment for this particular batch. He did recommend that I throw my plastic tubing away since it is a soft plastic and may be a potential source of contamination for subsequent batches. I spent a couple of bucks and bought new plastic tubing that I use for bottling.

I only had one batch fermenting at the time so cross-contamination of batches fermenting at the same time was not a concern to me. I was only concerned about subsequent batches.

Cheers!