It's a good idea to do something if for no other reason than keeping bugs from taking up residence inside the cozy little tunnels. However. if you seal it completely, you can trap moisture inside. The best approach I've seen is a roll of thin aluminum tape that is about 1" wide. You apply it to both ends of the panel, and then you roll a little tool across it (sort of like a pastry wheel) that puts tiny perforations in it. It keeps out the bugs but let's a little air circulate.

Here is a link that might be useful: Polycarbonate tape

The buildup of algae on the panel ends is of concern. How to prevent it is another story. I don't have experience with the tape, so I won't venture an opinion, but you can check out my previous posts with pics about the algae. Jim