Polyp Extension reason?

[rcpalmer1]

What do you think is the biggest reason for polyp extension. I have two tanks plumbed into one sump. Both tanks have similar lights and the water is exactly the same. Both tanks have similar powerheads for flow. One tank has better polyp extension than the other. So I'm just curious as to what other people have found as a contributing factor to have better polyp extension.

 

[Coralreefer1]

Could be correlated to a lot of different factors. Possible factors may be where the coral comes from geographically( Red Sea, Indonesia, Australia, Caribbean etc.) as well as coral reef ecosystem (lagoon, fringing reef, atoll, tide pool etc.). There still may minute changes in water chemistry, water clarity and how it can be altered through turbidity and gelbstoff. It still can be due to water flow as no two tanks are alike though they might be similar. It can also be a direct result of chemical warfare or other less destructive problems like snails, crabs and pods taking up residency on your corals. How about the age of your lights, intensity, Kelvin and heat emitted!
These are just starters. But all can effect corals from one tank to the next. The same thing holds true in the reefs of the world where a colony of Zoanthids, say in the Florida Keys , might look different to the next one a couple feet away from the other.

 

[jda]

Polyp extension in acropora/SPS is only NEEDED for gas exchange. If a coral does not need to exchange gasses, then it will not risk any damage (eating, nipping, etc.) just to have their polyps out. If you have two tanks on the same system with the same corals in each, then the difference is probably a nipping fish or invert. Blennies, angelfish (other than genicanthus), tangs are all nippers at times.

Don't chase PE.... it matters not and ends up being a fools errand in the end. Just watch for changes... if a normally hairy coral is all of a sudden barren, then check some stuff out. If a coral that usually does not have much PE is all of a sudden very hairy, then check stuff.

 

[rcpalmer1]

I'm not chasing polyp extension. I am just trying to expand my knowledge. Both tanks have had very good growth. I have some acro's that are within inches of each other that have different polyp extension. I am currently in a grow out contest. I see some that have the same piece of coral that have polyp extension and some that don't. I was watching a video a couple weeks ago and the person was showing how the same montipora and highlight grows different than in low light. I was just curious as if there was a similar factor that resulted in Polyp extension

 

[Charlie’s Frags]

Depends on the coral because different corals have different types of polyps. My tenuis have insane polyp extension but all my smooth skins have very little.