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taricha · 02/24/2016, 06:16 AM

file this under theories that connect dots.
Vitamin B12, Cyanobacteria, Cobalt, and Dinos.
Dinos are needy (auxotrophic). One crucial thing that Dinos can't make for themselves, but are dependent on is vitamin B12.
"the vitamin B1, B7, and B12 requirements of 41 strains of 27 HAB[harmful algae bloom] species (19 dinoflagellates) were investigated. All but one species (two strains) of harmful algae surveyed required vitamin B12." The one species in the study that doesn't: symbiodinium!

B12 levels have also been shown to correlate with dino bloom events and B12 depletion with the end of blooms,

Dinos are in competition for B12 with most of the rest of the algae kingdom too: "many algae are rich in vitamin B12, with some species, such as Porphyra yezoensis (Nori), containing as much cobalamin as liver"

So where does this vitamin B12 come from? It's rare, breaks down in sunlight, is needed by eukaryotes, but only prokaryotes make it, which makes it quite a valuable commodity. One of the most important producers of B12 - you guessed it - cyanobacteria. "the cyanobacterial contribution to the oceanic B12 supply may be ~ 50 times higher than the contribution of heterotrophic bacteria."

And to make B12, you have to have Cobalt. In some areas of the open ocean, Co has been found to limit the production of B12. Cobalt is also contained in soil, and in our salt mixes - 6 of 9 salt mixes tested above the detection limit which was significantly higher than NSW concentration of Cobalt.

Dinos need B12
Coral doesn't need B12
algae competes for B12
Cyano makes B12 out of Cobalt
salt water changes replace Co

on a separate note -
I turned off my skimmer 3 days ago, and I've looked through the microscope for hours and taken samples from all over my system: water column, deep dino territory, on the margins, healthy sand, all varieties of skimmer mixes etc.
I have not seen any microscopic dino grazers - or any evidence of them. I see live dinos and dead dinos, but no microlife eating dinos.
(I am aware that the presence of some bacteria can make dinos stop functioning, and I wouldn't be able to see that.)
I was really hoping to find an oxyrrhis or gyrodinium munching on some amphidinium. nothin.

02/24/2016, 06:16 AM	#3188
taricha Registered Member Join Date: Mar 2010 Location: NE Miss Posts: 608	file this under theories that connect dots. Vitamin B12, Cyanobacteria, Cobalt, and Dinos. Dinos are needy (auxotrophic). One crucial thing that Dinos can't make for themselves, but are dependent on is vitamin B12. "the vitamin B1, B7, and B12 requirements of 41 strains of 27 HAB[harmful algae bloom] species (19 dinoflagellates) were investigated. All but one species (two strains) of harmful algae surveyed required vitamin B12." The one species in the study that doesn't: symbiodinium! B12 levels have also been shown to correlate with dino bloom events and B12 depletion with the end of blooms, Dinos are in competition for B12 with most of the rest of the algae kingdom too: "many algae are rich in vitamin B12, with some species, such as Porphyra yezoensis (Nori), containing as much cobalamin as liver" So where does this vitamin B12 come from? It's rare, breaks down in sunlight, is needed by eukaryotes, but only prokaryotes make it, which makes it quite a valuable commodity. One of the most important producers of B12 - you guessed it - cyanobacteria. "the cyanobacterial contribution to the oceanic B12 supply may be ~ 50 times higher than the contribution of heterotrophic bacteria." And to make B12, you have to have Cobalt. In some areas of the open ocean, Co has been found to limit the production of B12. Cobalt is also contained in soil, and in our salt mixes - 6 of 9 salt mixes tested above the detection limit which was significantly higher than NSW concentration of Cobalt. Dinos need B12 Coral doesn't need B12 algae competes for B12 Cyano makes B12 out of Cobalt salt water changes replace Co on a separate note - I turned off my skimmer 3 days ago, and I've looked through the microscope for hours and taken samples from all over my system: water column, deep dino territory, on the margins, healthy sand, all varieties of skimmer mixes etc. I have not seen any microscopic dino grazers - or any evidence of them. I see live dinos and dead dinos, but no microlife eating dinos. (I am aware that the presence of some bacteria can make dinos stop functioning, and I wouldn't be able to see that.) I was really hoping to find an oxyrrhis or gyrodinium munching on some amphidinium. nothin.