Zoanthid Growth/Propogation Discussion


New member
I know we've all read the "Zoa Growth" threads with someone asking "OMG I just got this XXXX color zoa rock. How fast do they grow?" They're typically quite ambiguous and all they tell about their new zoas are they're "pretty".

I've been told by a friend that he noticed quickest growth out of small frags. 3-5 polyps.

Anyone noticed any trends? Small frags, large frags (10-15), colonies? Does the growth slow as the colony gets larger or does the growth continue or become faster as the colony better establishes itself?

I'm wondering if taking a small colony (~30 polyps) and cutting it into smaller pieces and spreading them out over a larger rock would increase the overall growth rate. Aside from the obvious increase in perimeter and thus available resources (area to bud off to), I'm curious if there is possibly something telling small groups of zoanthids to reproduce faster.


In Memoriam
I've always felt that growth is based on how many exist already. So a few polyps bud a few more, but a lot of them bud a lot of them.

As you pointed out though, the space around the frag is key, where a blanket of zoanthids can only grow along the outer rim. Rarely do I see new ones forming in the center and suddenly releasing them to drift in the current like polyp-bailout with other corals.

Growth rates vary, but I can't think of a single zoa that I've ever owned that grew so fast that I was impressed. They take their time and imcrease in numbers gradually.


New member
it may appear that a frag with only 3-5 polyps is growing/reproducing more rapidly because the growth is more noticeable. if you have a frag of 50+ polyps it will be harder to notice 10 or more polyps. with larger polyps you should get more growth because more are reproducing at the same time. small frags have fewer polyps that will reproduce.