I have been having the most frustrating time trying to grow phytoplankton this year. ISO, does nothing, it just immediately dies. Nanno will grow quite rapidly for 24-48 hours. Then within an hour, it clumps up and settles to the bottom of the bottle. If I split the cultures every day I can keep it going but I can not get a nice dense culture worthy of feeding to anything.
I thought I had replaced every possible point of failure.
I replaced the fertilizer,
I replaced the light bulbs.
I tried brighter lights.
I tried dimmer lights.
I tried higher salinity
I tried lower salinity
I replaced the salt mix
I started using RO water
I replaced the RO membranes
I replaced the bottles.
I replaced the air pump.
I ordered new cultures.
Nothing has helped one tiny bit. Then a few minutes ago, it just occurred to me.: "It is damn hot in my fish room. I am always sweaty when I finish playing with my fish, I wonder what the air temperature is." Turns out it is 29C. That is kind of warm. Could that be my problem? Could that cause cultures to grow for 24 hours and then crash?