Hi there,

Good question.  There are many reports/anecdotes of residual chloramine causing stalls or killing various fermentations (sourdough, beer, etc). Typical processes like letting the water stand overnight or using standard boiling practices will not “off-gas” chloramine, so those aren’t really good options.

What can you do?  

Option 1: Give it a try. The chloramine levels in your water will probably fluctuate and the dose matters. It seems that if you can’t smell or taste the “chlorine” in your tap water, then it is likely to work just fine in your starter. If you can smell it, then it might be a problem.  

Option 2: Use bottled water – at least to start a new starter. Sourdough starters are the most finicky early on, so if you use bottled water for the first week you have a high likelihood of getting the right families of yeast and bacteria to high enough concentrations.  Later feedings of the starter will likely be able to handle the chloramine in the tap water.  A good check would be to check that they are doubling in size between feedings.

Option 3: “Treat” the water to get rid of the chloramine.  A longer boil time (60 minutes) can get rid of the chloramine. Certain home water treatment units (carbon filters, reverse osmosis, UV) units can remove chloramine from your tap water – check with the manufacturer about specifics. 

Hope this helps! Best of luck with the sourdough!

Joy