I am a little late to this now three month old party you are throwing.
If you've not yet seen this article, perhaps give it a read. I do think getting a proper ID would be a good next step. Pressed to guess, I'd say you have a some blend of LC Amphids, small cell Amphids and maybe some Prorocentrum for good measure. All of these will happily coexist with cyano. It is a tough combo that can take months to turn around.
The only dino you can remedy with a quick fix is ostreopsis. The rest require time to build (or rebuild) surface competitor populations. Many of our efforts to "fight" or "kill" dinos don't last because those methods harm the competition as well.
Just curious, was this a dead rock start?
As the title suggests, this is intended as a short guide on what to do when you suspect dinoflagellates are trying to overtake your system. It is an attempt to boil down the protocols discussed across 11,000 posts in this "Are you Tired" thread...
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