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added instructions./guidance for starters
===Starters and Other Manufacturer Tips===
In the past, some yeast manufacturers (namely Wyeast) did not recommend making a starter for mixed cultures. Reasons varied from "throwing off the ratio of microbes" to "creating acetic acid". In regards to the first concern, throwing off the ratio of microbes will likely not be a real concern. It is possible that this will change the profile of the fermentation (for example the beer might turn out more sour because the lactic acid bacteria were allowed to grow more cells in the starter), but if treated properly all of the microbes will have a higher cell count after a starter is made, and yeast (both ''Brettanomyces'' and ''Saccharomyces'') will be more viable after a starter. Oxygen does not inhibit lactic acid bacteria in general, so this is generally not a concern.
In regards to the second concern above, oxygen does encourage acetic acid production in ''Brettanomyces'' (and some species of ''Lactobacillus'' such as ''L. plantarum''). However, a starter can be decanted to remove the starter beer if it smells highly acetic. Some brewers have reported not decanting the starter at all, and the small amount of acetic acid present doesn't make a large impact on the final beer.
In general, we recommend a 500-1000 mL starter (~1.040 OG with DME) for a 5 gallon batch. Run a stir plate on the lowest setting, or use occasional manual stirring with no automatic stirring. Do not use hops in the starter unless inhibiting the lactic acid bacteria is desired. One may want to have an anaerobic starter in the case that the lactic acid bacteria are especially weak, and the brewer wants to inhibit the yeast growth in the starter. Remember though that yeast needs oxygen in order to grow viable cells.
See the recommendations below from smaller yeast labs below for examples of how to treat mixed culture starters.
====[[The Yeast Bay]] on Mélange and Farmhouse Sour Ale====