Need help with ID disaster

[sailorman]

This growth seemed to come out of nowhere. What you are looking at grew in about 3 weeks after the rock was scrubbed clean.
All snails have died. The stuff is growing everywhere. It clogged up the overflow weir causing the tank to overflow. If anyone knows what this is it would be a great help to me so I can research how to treat it.

 

[shwareefer]

I'm going with hair (derbersia) or maybe bryopsis (but need to see the fillaments up close) plus some other shmeng growing in it. You have to have a nutrient imbalance and/or that rock is directly leaching (phosphate) to grow that fast.

The video looks possibly fernlike fillaments (bryopsis).

 

[G Santana]

My money is on GHA, what are your phosphate and nitrate numbers?

I battled it with Vibrant and Hydrogen peroxide. It took time but it works.

 

[sailorman]

Phosphate is high, 0.11 ppm. Haven’t checked that in months because it was always low,<0.03 ppm. Nitrate is nearly undetectable but that is normal. pH is high for some reason, 8.5. It usually is between 8.0-8.1. Specific gravity is spot on. Can’t read mg, Red Sea test kit always comes up high, 1600 ppm. Using Reef Crystals salt.