Dino ID help

[SomeKindOfOctopus]

Hi,

I've got some Dinos growing on a small patch of sand. Was hoping for some ID help. Best magnification I have is a USB microscope, hoping that's good enough.

The black line in the lower left is 40um (approximately)
Video:


From the motion I'm thinking Prorocentrum? They seem to mostly jerk back and forth. If they get isolated on their own they will spin in place sometimes.

 

[Reef and Dive]

To me looks more like Amphidinium.

 

[saltyhog]

Impossible to say for sure but the treatment is the same for both. Dosing silicates for a competing diatom bloom, keeping NO3 and PO4 up (5-10 and 0.06-0.12 respectively), dose phyto, manual removal when possible, add any other biodiversity any way you can.

Those two are the hardest to get rid of but are also less toxic (amphidinium isn't toxic prorocentrum is occasionaly).

 

[SomeKindOfOctopus]

Got it,

Thank you both for your help!

 

[taricha]

From the motion I'm thinking Prorocentrum?

they look prorocentrum to me too