Obtaining pure cyanophage stocks (plaque purification). 
Make a dilution series of the lysate (assume 104 to 105 PFU per mL in the plaque lysate). 
Repeat the plaque purification procedure 2 more times to ensure that the cyanophage isolated is clonal.
Repeat the plaque purification procedure again.
Finally, prepare a primary cyanophage stock using lysate from the final purification via method A "Liquid Amplification" OR method B "Plate Amplification" Method A: liquid amplification Method B: plate amplification Titer the final stock via plaque assay.
Cyanophage stocks stored at 4°C in the dark are stable for at least a year.
