nannochloropsis phytoplankton culture (questions)

[rayjay]

I light 24/7.
To measure the density I let it sit until the surface is completely motionless and I shine a 30 million candle power light on the stick and read the centimeters where I can no longer discern the spot on the stick.
Time to get to a density of 3.5 will vary with starting point and light duration and light intensity.
If the light isn't sufficient to produce the required density in about 8 days, 10 at most, I pour into another sterilized container through a 53 micron mesh and put back under the light source again.
If I don't clean out the container, any settlement can cause a crash before the culture gets to where I want it to be.
I buy mass packs that make four litres of f/2 and I store it in the refrigerator at 36°F. It has a limited shelf life according to FAF but I have gone over the limit quite a bit and many times, without any noticeable problem.