[Chlamydomonas] how to limit growth?

[Seppe Kuehn]

We are looking for a protocol for growing Chlamydomonas Reinhardtii  
under phototrophic conditions where the final cell density is limited  
to ~10^5 cells/mL.  We would like to do this without adversely  
effecting motility, metabolism, or overall health of the culture.     
We are currently working with the UTEX 2244 (mt+) strain (also known  
as CC-125) but are open to using other strains if necessary.  Thus  
far Sager's medium has worked best for our application so a simple  
modification to this medium that limits final cell density would be  
ideal.  Thank you!