For awhile now I've been growing Azolla in most of my ponds. What's Azolla? It's a small floating water plant.
I started it with a very small handful from another person. Just about two dozen tiny plants. If given the right environment, they grow so rapidly that they double their numbers in about two weeks...slower when conditions aren't ideal. But they're aggressive growers none-the-less. And they didn't need any help from me to do that. The fish waste from the koi, guppies, and tilapia seems to be all they fertilizer it needs.
My initial reasons for getting azolla, besides the fact that it was cool to look at, was to help shade the water in order to keep it a cooler temperature for the fish. Without the aid of shade, the shallow pond water heats up too high. Plus azolla helps filter waste from the water, again for fish health. None of my ponds have filter systems, so the plants do that vital job. After a few months I saw that I was getting an abundance of azolla, so I started looking into what other uses it could have. I was developing a resource, so how would I utilize it?
Chicken food: Most evenings I toss one jumbo handful of fresh azolla into the chicken pen. Sometimes I gather several handfuls for them. I don't hang around to see who eats it, but my morning it's gone.
Soil amendment/fertilizer/soil conditioner: I've read that adding azolla to compost or directly to the soil is a common practice. I haven't used it in the compost, simply because I already have lots of other green material available and I don't yet have bucketfuls of extra azolla to dispose of. But when working with dried out soil, such as during a drought period, I plan to till in some azolla last thing before calling it quits for the day. By the next morning the soil should be easier to work due to being moister and it accept water better (dry soil here tends to repel water). Being that the azolla is small individual plantlets, it's very easy to till in...or even scratch in by hand.
Fish food: I've read that fish will eat azolla. Honestly, I've never witnessed the fish eating it. But I do know that it took a long time for me to get it established in both the koi and the tilapia ponds. So I suspect they were consuming it. But now that it is well established, if indeed the fish are eating some, the azolla is out growing the fish's appetite for it.
Ok, azolla can be used as a livestock feed and a soil conditioner, or for fertilizer. They're good enough reasons to add it to this farm's resource list. It's a keeper.