I second the ulva. Mine comes and goes in spurts depending on how much I’m over feeding my fish. It’s a macro. Some tangs will devour the stuff. When a small piece breaks away from where ever it is in my tank you can see the disgust in my Orange Shoulders eyes..... SPOILED BRAT WONT TOUCH IT! Lol
I have only cerith, but more on the way and maybe some dead ones in the mail. I ordered a CUC package and it was mailed USPS and everything in USPS is currently FUBAR as far as I can tell. I now will have one of the most expensive CUC ever.