What is this yellow blob?

[ZoaSue]

Hi everyone,

I have been battling a cyano outbreak in my largest saltwater tank, and today this thing popped up, under a live rock. What is it? Egg? Pest? Alien?
I have been suctioning out the cyano, every other day.
Ammonia: light yellow (0-<.25 ppm)
Nitrate: light yellow (0-<5 ppm)
Nitrite: light blue (0-<.25 ppm)
Alkalinity: grape colored (~8-8.2)
Water for the tank is bought from the local fish store, pre-mixed. Salt is 1.24
Temperature ~78, I have a fan on the water (we live in S. Tex)

Occupants:
Corals: Kenya trees, mushrooms, xenias, gorgonians
feather dusters
2 nassarius snails
1 large turbo snail
~ 6 astrea snails
~4 hermit crabs
2 emerald crabs

 

[KrisReef]

Appears to be a bubble algae.

 

[unclejed]

This worked for me in less than 24 hours...