phytoplankton turning white

[aquatictec]

It only happens when we split our cultures
We use sterilized aerated salt water at a s.g of 1.023
the cultures often turn white within hours of splitting them
It only happens when we split them
It has happened to nano, tetraselmis, and iso
We have tried various light sources

sometimes the cultures turn back green or brown
sometimes they die

 

[ichthyogeek]

have you tried adding fertilizer? That's the only thing that seems to be missing. What fertilizer are you adding to the new salt water? I used the blue miracle grow powder, and it turned a mixed culture (started from live phyto-feast), white a few days later.

It might also be a predator problem. Have you analyzed the white cells under a microscope?

 

[aquatictec]

f/2 formula
Have scoped
only happens when split

 

[gogo7]

i've got some pointers. i'm only culturing litres at a time....hope they help...i find glass retains heat, and over heats and cooks the phtyo. turns white..i've used thirteen watt cfls to culture three diff. sp. nanno, tetra and the unkillable dunaliella. faf has a strain that i highly recommend to anyone. use plastic bottles, garbage bags, tubes. i use two litre clear pop bottles,no air. lid on with a hole in the top for an air tube if needed. daily swirlies, this is important .... unless i wanna increase production. if i let the duna go too long without food, it starts to brown. ten to twenty five percent addition of fresh water fert. at two drops per hundred mils. with increase of light levels ( two cfls) brings it back. here in canada i use all the free light i can get..i use the window sill. a south facing window that is draughty in january. temps get low. tetra and duna can handle the abuse, but nannochlropsis is tempermental ime. all three can handle swings in sg. i've learned to siphon off the top with dedicated air line that gets bleached every now and then. the ciliates accumulate at the bottom mostly. i've experienced ciliate blooms that come and go in twenty four hours.
sorry if it sounds like i'm rambling but i had to work monday. .