what does it mean if a coral turns brown?

[tang daddy]

when a coral browns it is usually because of excess nutrients, But when acros get moved to a different system and turn brown it is getting use to its new enviroment. I've had frags stay brown for up to 1 yr before colouring up.

When the sps get stressed from a new system or high nutrients it will drop it's zooanthelia basically dropping some of it's colours.... it can regain colours but needs time. Low nutrient systems have brighter colour sps because they dont feed on nutrients as much, also sps use light to convert it to food which forms on their body in a brownish colour....

You can do a search on google to find out more on how these animals feed, grow it's really amazing....