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''P. damnosus'' is sensitive to temperature and pH. It is unable to grow at a pH of 8 or higher or at 35°C. The optimal growth occurs at 22°C and 5.5 pH. ''P. damnosus'' is sensitive to environments that contain NaCl, and will not grow with concentrations of 4% NaCl <ref name="ucdavis"></ref>.
One study showed that optimal growth was observed in [http://www.neogen.com/Acumedia/pdf/ProdInfo/7406_PI.pdf MRS media] with an initial pH of 6.7, and allowed to ferment down to a final pH of 4.14 , which occurred naturally from fermentation. The addition of bacteriological peptone, MnSO4, and Tween 80 also increased activity <ref>[http://www.ncbi.nlm.nih.gov/pubmed/11851822 Nel HA, Bauer R, Vandamme EJ, Dicks LM. Growth optimization of Pediococcus damnosus NCFB 1832 and the influence of pH and nutrients on the production of pediocin PD-1. Department of Microbiology, University of Stellenbosch, Stellenbosch, South Africa. Dec 2001.]</ref>.
Maximum cell densities of ''Pediococcus'' and ''Lacto'' are around 50-80 million cells/mL. Since they tend to have high nutrient demands, this number varies based on the conditions of the propogation propagation <ref>[https://www.reddit.com/r/Homebrewing/comments/3qp7b7/advanced_brewers_round_table_neva_parker_white/cwh7iqq Neva Parker, Reddit thread. 10/29/2015.]</ref>.
Although more experiments and probably needed, agitation is believed to be an important factor for any species of microbe (yeast and bacteria). Gentle stirring on a stir plate or orbital shaker, or frequent gentle manual agitation leads to faster growth and a higher number of organisms. Agitation keeps the microbes in solution. It also maximizes the microbes' access to nutrients and disperses waste evenly. In a non-agitated starter, the microbes are limited to the diffusion rate of nutrients, leading to a slower and more stressful growth <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1168024059892473/?comment_id=1174865305875015&reply_comment_id=1176092372418975&total_comments=1&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Bryan Heit about starters and agitation. 11/09/2015.]</ref>. Although ''Pediococcus'' are aerotolerant and oxygen usually does not negatively affect their growth, it is also generally not needed. Therefore, it is generally best practice to seal the starter with an airlock.