Sponge, Tunicate????
 

So what's this thing? It's growing really quickly
http://www.canreef.com/vbulletin/pic...&pictureid=931

Some sort of sponge :)

I have the same thing in my tank and I have been told that its good stuff
http://i292.photobucket.com/albums/m...9032009626.jpg

new but handy = sponge

reefy = colonial tunicate

both good :biggrin:

What's the difference between them?

Tunicates are higher up the evolutionary ladder, they have organs for circulation, digestion and even have a spinal cord. Sponges have none of that.

Visually, sponges are usually uniform in structure (I mean what makes up their structure). Closeup they have various openings to create water currents to help bring in food and remove waste.

Colonial tunicates use the same idea, they create an incurrent and excurrent siphon for flow. However when you look closely, you can see what almost looks like "veins" within. Tunicates also look more gelatinous as they are enclosed within a thin membrane.

^^
Great info. Thanks Christy.

+1