Not to take away from these beauties, but certain species of Caulerpas should be avoided, except in a fuge or a macro specific tank. Caulerpas are illegal in some places, so be familiar with your local ordinances before purchasing. Do not rely on the “seller” for this information. Just because they will ship it to you, doesn’t mean they are acting within the law.tegory. Some of these are also common when a tank is new and only really become a nuisance when they become established.