White buildup on live rock

[FeatherstoneReefer]

I will attach pictures.
30 gallon tank
hang on back protein skimmer
sponge filter
25lbs of live rock
live sand
crushed coral
two powerbeads (surface agitation & one for flow)
heater
coralife t5 bulbs (white spectrum and blue spectrum but I leave the blue on most of the time because it looks nicer)
galaxia
Xenia
toxic green zoanthid
duncan
fuzzy mushroom
monti
GSP
two juvenile clowns
one juvenile benggai
one juvenile royal gramma
one juvenile dwarf angel
one royal urchin

I have a white buildup on my live rock that appeared sometime between 4:00am and 3:00pm today
This week I introduced the gramma and the benggai. 2 days later I introduced the urchin.
It does not appear that my live rock is "turning white" it looks like a buildup of some kind.
again I will attack pictures

 

[sbash]

A couple of possibilities off the top of my head:

First, the sea urchin could have been munching on those areas and 'cleaned' the rock. Look into how they eat and this will make sense...
Second, sponges! are the white spots squishy? If so, they are likely just sponges, nothing to worry about.

Either way if the corals and fish look happy, I doubt it is anything to worry about. But I would lean toward spots where the urchin was eating.

 

[FeatherstoneReefer]

A couple of possibilities off the top of my head:

First, the sea urchin could have been munching on those areas and 'cleaned' the rock. Look into how they eat and this will make sense...
Second, sponges! are the white spots squishy? If so, they are likely just sponges, nothing to worry about.

Either way if the corals and fish look happy, I doubt it is anything to worry about. But I would lean toward spots where the urchin was eating.

now that I think about it, the spots of white are located on the regions where I placed the urchin

 

[FeatherstoneReefer]

A couple of possibilities off the top of my head:

First, the sea urchin could have been munching on those areas and 'cleaned' the rock. Look into how they eat and this will make sense...
Second, sponges! are the white spots squishy? If so, they are likely just sponges, nothing to worry about.

Either way if the corals and fish look happy, I doubt it is anything to worry about. But I would lean toward spots where the urchin was eating.

Is it a bag thing that the urchin is eating the crud off the rocks? does it have a beneficial value for the tank not to clean it?

 

[Maritimer]

The urchin will clean algae here or there, and the algae will re-colonize.

I'd consider that all a pretty good thing.

~Bruce