Can anyone help ID this please?

[Reef Apprentice Cicimi]

We noticed these white things coming out between a few of our corals and it appears they are spreading throughout the rocks. Does anyone know what this is? Where does it come from? How do I control/get rid of them?

 

[Aldrinlights]

Please always list what size tank it is and the age of your aquarium. Parameters will help as well. The bottom picture looks like Hydroids. Not really a big problem usually. Your zoas looks like something else but i dont know for sure. Did you dip your coral frag before putting it in your tank? Always always always use coral dip. I use Coral RX

 

[JGT]

Sponges. Harmless.

 

[Sharkbait19]

Sponge

 

[Reef Apprentice Cicimi]

Please always list what size tank it is and the age of your aquarium. Parameters will help as well. The bottom picture looks like Hydroids. Not really a big problem usually. Your zoas looks like something else but i dont know for sure. Did you dip your coral frag before putting it in your tank? Always always always use coral dip. I use Coral RX

Our tank is 125 gallons and sump is 39 gallons. Tank has been up and running for over 2 years. Current parameters are Salinty = 1.024 , Alk = 8, Calcium = 350, Magnesium = 1270, pH = 7.93, temp ranges = 75.9 - 76.3F. Frags have been in tank for over 6 months and all were dipped using Coralrx as well. Thank you for your response and any advice is appreciated.

 

[Aldrinlights]

Our tank is 125 gallons and sump is 39 gallons. Tank has been up and running for over 2 years. Current parameters are Salinty = 1.024 , Alk = 8, Calcium = 350, Magnesium = 1270, pH = 7.93, temp ranges = 75.9 - 76.3F. Frags have been in tank for over 6 months and all were dipped using Coralrx as well. Thank you for your response and any advice is appreciated.

Nice tank. Thanks for sharing. Your temperature and salinity is a bit low. Most would recommend running it around 78 to 80 degrees. And salinity 1.026 are you running a UV filter?