UF thanks for your ideas and the added information on the subject of duckweed. Hopefully this information along with the other threads here on duckweed will help others decide if duckweed is worth a try for them.
Here is where I started in my thoughts on the subject of duckweed.
#1, Duckweed is a possible miracle free food source for fish, like manna from heaven according to many threads I have read in various places.
#2, Duckweed is the "devil" and will take over your AP system and spread to every nook and cranny, overtaking everything else, according to others.
Now that we have had this discussion, here are my thoughts on duckweed.
#1, Duckweed while seemingly easy to grow and relatively cheap to produce, (compared to some other fish foods), is not a miracle food that will replace all of your feed cost with a FREE food. Duckweed can however, be beneficial if feed as a supplement along with other quality fish feeds.
#2, Whether duckweed is economical or worth the time and effort and expense to grow for YOU, is going to depend on your individual situation and many local, environmental, economical, etc. circumstances.
#3, Thus far based on the limited information we have on duckweed, it would be difficult to accurately put a number on what the exact $$$ value of duckweed is.
To be quite honest, I do not have the needed time or desire to carry out such an exhaustive study to determine this exact $$$ amount of value in duckweed. This is why I was hoping to learn this information from some of you who are actively using and feeding DW. Everyone is certainly free to make their own decision, as to the benefits of duckweed in their particular AP system. What I have seen, thus far, has led me to believe, if I have the spare time to experiment with duckweed it would be worth the effort, as there is potential for some benefits.
Now having said that, I would not have high hopes going into that experiment of large $$$ gains in feed production. My best hopes in such an experiment, would be to provide a supplement that may slightly lower my feed cost, but more importantly, would provide me with healthier fish. But that is just me, you need to make up your own mind based on your unique situation.
Again UF, thank you for your informative post on the subject. As for labeling my duckweed "ORGANIC", yea I will get right on that, and wait for the USDA folks to show up, handcuffs in hand!!!!