Hello to all lovers of marine plants. It is extremely difficult to get plants for marine aquarium in our country. About 10 years ago it was a little easier and several species used in sampas were available to amateurs. But now everything has changed and even hetamorpha has become scarce. Recently I was given a bush of gracilaria. It is a huge jewel for me. It has increased in size and I have divided it into several parts. However, not in all aquariums it remains a beautiful and red plant. Sometimes it becomes paler. It loses its red color. Why? What do red plants need in an aquarium?