Growth in tank

Question
QUESTION: My 55 gallon tank (4years old) has begun producing multiple growths as noted in the picture below. The first one was present in the tank for about a year at the same size. Over the past few months, we have noticed many more popping up. Cream colored and about the size of a dime. Any idea what these are and are they safe for the tank?? Thank you in advance. Nicci

ANSWER: Hi Nicci:

From what you have described it sounds like they are harmless sponges.

I wish you the best of luck with all your saltwater aquarium endeavors.

Regards,
David

All Experts - Editor

http://www.ocreef.com / OC Reef Aquatics - Director of Operations



---------- FOLLOW-UP ----------


Pic 1  

Pic 2   QUESTION: David,
Thank you for the response. After I hit the send button yesterday, I realized I had not enclosed pics. Please review and let me know if you still feel they are harmless sponges. There are quite a few in the tank in varying stages of development and some have holes on the sides of them?? Thanks in advance for your time and expertise.

Answer
Hi Nicci:

From looking at the images, I can confirm that it's definitely sponges. These are a welcomed addition to a reef aquarium. You have nothing to worry about.

In the reef aquarium hobby, species of blue, yellow, and red sponges are highly sought after.

In nature, in the oceans coral reef's, sponges are a food item for many types of fish, including many species of Angel fish.

Regards,
David