Growing Duckweed for Fish Food

[Chelsea Brannan]

any one growing their own duck weed for additional fish food? How is it working out for you? any tricks?

Duckweed gardening here!

[Roger Baldwin]

I have been growing duck weed in a tank attached to my sump tank with a bridge siphon for about six months, my pump pulls water outta the duckweed tank into the fish tank.  It grows like crazy, I harvest at least a cup a day out of the tank.  Mostly I use it to feed my chickens, they love the stuff!  I do give my fish a hand full in the morning before there regular feed, they eat it when they are hungry, but they prefer fish food.  It is a good supplement to add diversity to their diet but I have not seen much of a decrease in the amount of food I have to feed them.  I had to remove the sponge like filter from my pump because it kept getting clogged, and if I give the fish too much the stems end up in the grow beds, the same with giving them too much of any food.

[Converse]

  I grow my duckweed in a separate pool.  We feed our duckweed to all our farm fowl, or pigs and fish.  We even freeze the extra for a food source in the winter.  Because it gets very cold here in winter, I also bring in some duckweed into the house for overwintering in a tank to be sure I have some to restart  massive duckweed propagation in the Spring.  So far we have been able to keep it alive in our greenhouse through the winter any way.

[Chelsea Brannan]

This is great news! I am happy to hear this, I have some in a bucket that I thought I'd try to grow, we do have chickens and I'm sure if the fish don't eat it the chickens will! I heard it multiplies fast so we'll see what happens. Thanks for the input! 

[Reese K]

I put a large amount of duckweed and azola along with water hyacinth into my 200 gal fish tank with about 30 baby Tilapia and it is going away. I dont know if the fish are eating it or if something else is happening. the hyacinth is doing well it even flowered my other plants are doing well also other than slight iron deficiency but the amount of duckweed has shrank considerably. the fish seem to have no interest in the food im providing any ideas.

[Moe]

I have a duckweed station. I went through a lot of work to set it up with air pumps to drive Mosquitos away. Now when I feed it to the fish, the over flow going to the ST has a lot of green stuff in it. I put a mesh bag on the pipe going in the ST and I have to rinse it every day. I do not know what to do with that green stuff. Any suggestions?

[Hank Paloci]

Pretty sure the green stuff is root like or otherwise connected to duckweed. My tilapia eat it with the duckweed and seems to be good stuff.

[Moe]

I have the same issue.  if I do not feed the duckweed to the fish, the water is pretty clear.  if I start to feed duckweed to the fish, the water is dark and pretty green.  I can not see the fish.  the ST's walls are green and so on.  I went through a lot to grow, setup duckweed stations.  I have plenty of duckweed growing.  I am not going to let it go to waste.  it can not be bad!!, I hope!

[BK]

We have duckweed growing in a separate (but connected) tank. That tank overflows back into the fish tank.  The water is drawn from about halfway down the tank; since the duckweed all floats there is no need to filter the water draining back to the fish.  I have noticed some algae growing amidst the duckweed from time to time.  Not a big problem, our tilapia eat that too, but algae robs O2 from the water so we're glad that the duckweed almost completely overpowers the algae.  Some of the green that others are noticing could also be algae growing along with the duckweed.  The tilapia used to eat the duckweed almost preferentially but the novelty has worn off.  They eat it, but usually after the commercial food is consumed.  I limit the amount of duckweed I feed each time but inevitably a little bit ends up in the sponge filter.

[Moe]

hi,

my comment is regarding the tilapia preferring the commercial food over the duckweed. I have the same issue.  Could it be that the commercial food is "junk" food full of sugar and GMO stuff!  They run "swim" for the commercial stuff and let the duckweed float and eventually leave the fish tank to the sump tank.  Thanks

[Jeff S]

The way I've heard it duckweed is high in protein which is good for fish growth. I tried growing it in the past with mixed results. It did grow but not as fast as everyone said. I had an IBC covered with it and put in a few hundred fingerlings. It disappeared in just a few days. Turned out to be more trouble than it was worth.

[MikeH]

We have had very good luck with duckweed. We started with just a half cup or so and now have the top from an IBC filled with it. We give a healthy handful to our fish and chickens everyday. It was so thick in places, almost an inch.
We flow water very slowly through it like a DWC and have a layer of burlap covering it for shade (about 3' above it). We got lucky by accident. Either way though it grows very fast.

[Moe]

i have mine growing in complete sun. like Arizona sun. and it is growing very well.