Sunny D's haven't grown new polyps in over a year!

[Mummy Dust]

Hello, I've had a frag of sunny d's for over a year now and they have completely ceased to grow new polyps.  They initially were growing just fine, doubling the number of polyps. They look fine to my eye but I could definitely use some input.  Water parameters are excellent. I wouldn't be asking otherwise! 🙂 Anyone have any advice? A pic for your perusal:

[Clown79]

What's the nutrient levels in the tank?

[NoOneLikesADryTang]

It's weird how they grow at different rates, in different tanks... I grow Sunny D's very slowly, but others like Bam Bams and Devil's Armor I have coming out my ears. I also have others such as utter chaos and blue hornets that seem to grow a moderate pace. I'd love to hear others thoughts this. 

[DarkMagic]

If you have a dozen colonies, half will grow, a quarter will not change, and a quarter will shrink. Roughly my experience with zoas and pallys. I can’t make heads or tails of it. 

[Daniel91]

Yeah, those fellas look happy but some zoas just refuse to grow, no matter where you keep your parameters and nutrients.

 

Zoas tend to like a “dirtier” tank, so take that into consideration 😉

[ninjamyst]

they dont look happy.  they are spread out and not close together.  Sunny D are FAST growers and like lots of high light and high flow and high nutrients.

[hypostatic]

try giving them some reef roids

[mcarroll]

...what @Clown79 said. 🙂