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The amount of growth that occurs in a starter is an unknown unless the brewer can do a cell count. Matt Miller of Sour Beer Blog and Richard Preiss of Escarpment Yeast Labs advise that if ideal growth (1-2 billion cells/mL) can be achieved (for example by using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's starter procedure]] or MRS media), then pitching as little as 100-125 mL of fresh ''Lactobacillus'' starter for 5 gallons of beer can achieve desirable acidity within 24 hours <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1180630378631841/?comment_id=1180733761954836&reply_comment_id=1180740128620866&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Richard Preiss on MTF regarding Lacto starters. 11/19/2015.]</ref><ref name="sbb2.0"></ref>. Moderately ideal growth in a starter results in around 500 million cells/mL, resulting in a 400 mL starter for 5 gallons, and low growth results in around 100 million cells/mL, resulting in a 2 liter starter for 5 gallons, according to Matt Miller (see [http://sourbeerblog.com/lactobacillus-2-0-advanced-techniques-for-fast-souring-beer/ Matt Miller's article] for more details) <ref name="sbb2.0"></ref>. If the amount of growth cannot be accurately determined by cell counting under a microscope, then pitching 0.5-1 liter of fresh ''Lactobacillus'' starter culture per 5 gallons of wort ensures that an adequate number of cells will be pitched.
Another thing to consider is that achieving a pH of 4 as fast as possible is advisable for preventing off-flavors from contaminating microbes <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1180630378631841/?comment_id=1181674265194119&reply_comment_id=1181715048523374&comment_tracking=%7B%22tn%22%3A%22R7%22%7D Conversation with Bryan of Sui Generis Blog on MTF regarding speed of acid production with Lacto. 11/20/2015.]</ref>. Larger pitch rates tend to achieve a lower pH faster <ref name="heit_lacto_startersbryan_lacto_starters"></ref>. Therefore, unless using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's starter procedure]], pitching 0.5-1 liters of starter for 5 gallons of wort is advisable in general. Even when using [[Lactobacillus#Samuel_Aeschlimann.27s_Starter_Procedures|Samuel Aeschlimann's starter procedure]], over-pitching ''Lactobacillus'' is not a concern (pitching an overly massive starter wort could produce undesirable flavors), so the same pitch rate should still be considered unless the brewer is confident that high growth rate has been achieved in the starter. Other factors that might affect the effectiveness of a volume based starter is the species/strain of the ''Lactobacillus'' being used, how much yeast contamination has occurred, and how old the ''Lactobacillus'' starter is. Some species/strains may require a larger volume of starter, as well as if yeast has contaminated the starter or wort (see [[Lactobacillus#100.25_Lactobacillus_Fermentation|100% Lactobacillus Fermentation]]). If a ''Lactobacillus'' culture is older than 1 month, then a fresh starter should be made. Keeping a separate Erlenmeyer flask for ''Lactobacillus'' starters can help to prevent yeast contamination <ref>Private correspondence with Richard Preiss to Dan Pixley. 11/20/2015.]</ref>.
Starter mediums that brewers have used include unhopped DME wort starters and apple juice starters. These tend to be adequate for many brewers. However, [https://eurekabrewing.wordpress.com/2015/05/18/evaluate-starter-media-to-propagate-lactobacillus-sp/ Samuel Aeschlimann from Eureka Brewing Blog] showed that using DME with a little bit of apple juice, chalk, and yeast nutrients provides close to optimal cell densities that match MRS media cell densities.
# The starter should be held at the temperature best suited for the culture as shown in the [[Lactobacillus#Culture_Charts|Culture Charts]].
# Reference the above [[Lactobacillus#Culture_Charts|Culture Charts]] for how long the starter should be incubated for before pitching. If a stir plate is not used, one indication that the starter is done will be when the top of the starter begins to clear <ref name="Sam_starter2">[https://www.facebook.com/groups/MilkTheFunk/permalink/1131778916850321/?comment_id=1131806746847538&offset=0&total_comments=6&comment_tracking=%7B%22tn%22%3A%22R2%22%7D Conversation with Sam Aeschlimann of Eureka Brewing Blog on MTF. 08/20/2015.]</ref>.
# The chalk is not desirable to pitch into the beer because of its buffering effect. The chalk will sediment within hours of being added to the starter, or if a stir plate is used, a couple of hours after the stir plate is turned off <ref>[https://en.wikipedia.org/wiki/Stokes%27_law Stokes' law. Wikipedia. retrieved 09/24/2015.]</ref><ref name="Sam_starter2"></ref>. The ''Lactobacillus'' should stay in suspension for at least a day or two after the starter is done, so swirling the starter isn't necessary, although it is certainly an option. If the starter is swirled, allow a couple of hours for the chalk to sediment out again. After the chalk sediments to the bottom of the flask, pour all of the liquid from the top of the starter into the wort/beer, and leave the chalk sediment behind. Avoid cold crashing the starter because it can have an adverse effect on the bacteria's health <ref name="heit_lacto_startersbryan_lacto_starters">[http://suigenerisbrewing.blogspot.ca/2015/05/lacto-starters.html Heit, Bryan. "Lacto Starters. " Bryan from Sui Generis Blog. Retrieved 6/15/2015.]</ref><ref name="sam_starter"></ref>.
See [http://suigenerisbrewing.blogspot.ca/2015/05/lacto-starters.html ''Lacto Starters'', by Bryan of Sui Generis blog] for additional information on ''Lactobacillus'' starters.