Why do gorgs attract dinos at the tips?

[sneeyatch]

It seems that maybe once a month or so all of my gorgs attract dinos at their tips. Sometimes the duration varies a little but I was just wondering why this happens?

It may be a water quality issue that I'm not aware of - although when I test everything comes back within an acceptable range.

It's more irritating than anything to me as the polyps won't open all the way when this happens.

Anyway - any advice or thoughts would be appreciated.

 

[pbnj]

You wouldn't happen to have an algae covered powerhead pointed at the gorgs, would you? That would do it.

 

[sneeyatch]

The powerheads are pretty far away from them actually. They do have the typical coralline and filamentous algae growing on them.