Diatoms or something else?

[3rdMoon]

How do I know if my “ugly stage” diatoms are actually just diatoms and not something else? The tanks been up for almost 5 months. My nitrates are usually 0 and phos are .3 Initially I was vacuuming the sand weekly but was told not to bother by a reefer buddy. He said it was typical ugly stage diatoms and to just wait it out. So... I have been. I’ve read recently tho where, with low nutrients, dino’s and cyano can take hold. And that dino’s often look a bit like diatoms. Also, when I stir up the sand it kinda clumps up like kitty litter. Can anyone give me some insight?

 

[Reefer1978]

I don't think it's diatoms. Judging by the color and tiny bit of fuzziness in the video, I'd say hair algae.

Your Nitrates and Phosphates seem out of balance to me. You should work on lowering P and Raising N a bit.