Doesn't look like dino's but it sure is bubbly! Do you have a microscope to check? (even a toy)

Click the #chrysophytes tag or check out @reeferfoxx's thread on the topic.

Check out the accuracy/error rate of your test kits. Considering that, your readings may be close to actual zero. If I'm right, you might want to keep levels just a little higher. Having the macro algae's demand for nutrients on the system might be the problem. Such a new tank really shouldn't need it anyway.

Why so much light/Why not just LED or just T5? Start with a free lux meter app, get some resdings, and we'll go from there.

What are your tank's dimensions?

So all of your CUC are helping with this algae? Seems like a small crew, but not sure of the tank size.

Dose No3 and PO4 into your water change water up to your minimum levels so neither one bottoms out during siphoning.

Hopefully you're describing something like #chrysophytes+cyano or better. Could be dino's though.

Pics will help. Even better, get a sample under a microscope (even a toy) and take some pics.

I'd bet on "And" not "or". Siphon and remove.

Y'all are just the best. awesome!

You didn't kill em. These are what we are pretty confident are #chrysophytes and they always appear motionless.

check this thread for them

Is there movement?
If there is no movement, then this tiny circles embedded in mucus looks like probably #chrysophytes

This worked for me.....definitely not dino's....at least not mostly. Maybe #chrysophytes?

(I could be wrong....you'll not my name is not included with ID results in those searches. )

Manual removal as-needed to keep corals safe while you're dealing with dinos. Check out old threads on the #chrysophytes tag and @reeferfoxx's chrysophyte thread. They may even give up while you're clearing up the dino's.

#Chrysophytes @reeferfoxx ?

(Good link!! Just for anyone following after this.... #chrysophytes are not a fungus, but an algae. You can click that #tag to find other posts that have been similarly tagged in the past, BTW.)

Either run a R2R search for the term or hit this tag: #chrysophytes

(or both!)

Can you post a full tank shot that also shows the scene in this pic? I'm having a hard time seeing this as diatoms (even if it is). LOL

Color would suggest #chrysophytes (which are diatom-like in some ways), but the photo still doesn't have enough detail to say for sure.

Diatoms should also not look green....is that color in the photo real?

If you can, I'd like to also see results of a "shake test" for confirmation. (lots of details for testing on the dino sticky thread...even for cyano too)

Put a sample in a vial, shake it up to homogenize it....leave it alone (ideally under a light) and see if it regroups in a mass or if it stays shaken up. Dino's are the only common thing that will regroup. Cyano or diatoms will not.