Sorry for the delayed reply.To be honest I don't have the knowledge to answer your question. I did read that their eyesight is quite good, but with all the duckweed on the pond you ask good question. Perhaps someone knowledgeable will see the comments and answer your question. Should I learn the answer I will post it in the comments here so that you can read it. Thanks for your interest, sorry I am not able to answer your question.
