Did I fail phytoplankton breeding?

[Anemoneee]

I was able to find a nice dark green phytoplankton batch from a fellow reefer. Great guy provided me with fertilizer for me to try and breed.
On Thursday is nice and green. 4 days later I see it more yellowish.

I follow instructions from people on YouTube. Sterilized inside and straw with rubbing alcohol.
Pour in close salinity salt water compare to the batch.
And leave the light and bubble running 24/7.

So my question is did I failed the batch already?
Which step did I do wrong?
Can I still salvage it?

Thank you all

Sent from my ONEPLUS A6013 using Tapatalk