Is this normal behavior for a colt coral?

[GMH320]

Everytime I feed live brine shrimp to the fish, my colt coral completely retracts (branches and polyps) for several hours, then slowly reopens. What could cause this?

 

[davelin315]

Everything including the brine shrimp are whizzing around the tank and bumping the colt coral, causing it's polyps to retract. A few polyps might be lucky enough to ensnare a couple of small brine shrimp and eat them, but mainly it's just the agitation in the water causing the colt to protect it's delicate polyps. Mine does the same thing anytime I feed, or even if I direct some current it's not used to at it.

 

[GMH320]

Thanks Dave, Do you think a gentle current is better overall, I may have to relocate it.