Question about my anacharis

Hello and I am back again with another question. I have ordered some anacharis online and they arrived a looking sort of olive colored. I put them with weights attached right away in my pond. That was 3 days ago. The Anacharis still looks olive colored but some of the stems are starting to look a little greener.

Question one is: Is there something wrong with the plants?

Question number two: What can I do to improve the condition of the plants?

Thanks in advance for your help. Carla