Tetraselmus culture crash

[TWYOUNG]

Can anyone help with why my Tetraselmus culture appears to have immediately died. I received it yesterday and although it was considerably lighter colored than the nanno I usually work with, a microscope verified it was very much alive with lots of movement. Diluted it 50/50 with 1.025 sp. gr. sw, in two separate bottles, added F2 and aeration. This morning BOTH bottles were clear and colorless with tetra settled to the bottom. I swirled it around to mix and took some samples which showed clumping and very little movement.

 

[TWYOUNG]

Can anyone help with why my Tetraselmus culture appears to have immediately died. I received it yesterday and although it was considerably lighter colored than the nanno I usually work with, a microscope verified it was very much alive with lots of movement. Diluted it 50/50 with 1.025 sp. gr. sw, in two separate bottles, added F2 and aeration. This morning BOTH bottles were clear and colorless with tetra settled to the bottom. I swirled it around to mix and took some samples which showed clumping and very little movement.

It's possible I may still have a living culture. Haven't scoped it again yet but a faint green color has returned.

 

[TWYOUNG]

This was Tues morning. The two on right are the Tetra and the far right one I swirled around to mix before the pic