Problems GROWING DUCKWEED On A Small Scale (Homestead Aquaculture) 

I’m growing duckweed in 100 gallon stock tanks in Hawaii to supplement feeding my laying hens. I have worked through some problems but things are much better now. Things to watch out for; 1. Water temperature, intense tropical sun can make the water way too hot during the summer. I put up 70% shade screen raised up about 3 feet above the tanks for airflow, this made a huge difference in keep the water below 79 degrees. 2. Water Ph, some of my tank got too alkaline. I check the water ph with litmus test strip and adjust the water ph accordingly. Municipal water is super alkaline and just plain nasty stuff. I collect rain water or take water from a steam on the property now. 3. Nutrients. In the beginning it was hard to figure out how much to feed the duckweed , especially before figuring the above problems. I have a catchment system to collect the urine for one of my horses. I use about 1 quart of urine diluted 1 gallon of rain water and sprinkle it evenly over three stock tanks every day, about once a week I mix in some castings from my worm bin to add other nutrients. Filtering through a fine mesh is necessary so the watering can rose does not plug up. The weed loves this feeding schedule! 4. adding air air bubblers keeps the water on the bottom of the tank from building up methane gas and oxygenates the water and helps to divide the duckweed. The water smells way better now and I feel better about feeding the weed to my hens. I alway rinse the weed with a garden hose in the mesh basket strainer and drip dry for a hour before feed in to the hens.

Other youtubers tested and found it grows best in the shade. I have had trouble growing it too. I grow it in buckets with fish waste water. This summer i will change the water every 2 or 3 weeks to replenish nitrogen. Duckweed is great food for goldfish and turtles.

I'm also one of those few who can't get duckweed to grow. Apparently I have too much water movement.

Awesome! I just started growing them in a bucket hoping they will thrive here in the desert. You can probably use chicken wire tied into a cylinder as a "safe haven" from the fish, this way there's a symbiotic benefit to having them in your pond but not risk losing them all...

What your lacking is nitrogen, we use cow manure. If your neighbors have cows or pigs, ask to scoop up a 5-gallon bucket full and you'll be able to feed your duck weed. Nitrogen is the #1 nutrient that duck weeds needs, the soil and the grain waste wash water just doesn't have enough nitrogen for good growth. What I would suggest if you don't have access to manure, is place a large container alongside your fish tank just slightly higher. Run a small pump that will pump your fish water to the duck weed container and have it overflow back to the fish tank. Not only will you feed your duck weed it will take that nitrogen/ammonia and cleaner water will flow back to the fish. Thats why its working in your guppy tank, there nitrogen load from the fish, but for this system to work you need a large amount of fish. If your juts running a handful of fish they never will produce enough waste to feed the duck weed.

I remember a pond full of Duck Weed as a child. The banks of the pond were hopping with frogs and slithering with Garter Snakes. It was such a vibrant environment, now it is a subdivision. No evidence of a pond.

Just add a pump to extract some of the waste water from your fish and feed that to the Duckweed that has no fish in it.

Great video, I've only just now found your channel and I'm really impressed with it! A lot of what I know about duckweed is its potential for a source of bioremediation, renewable energy, and (of course) a prolific protein source. However, based upon their application there are different species that are recommended by the literature. If you mentioned what species you're using in the video, then I apologize I must have missed it, but if not then maybe switching the species (from what I've read, those within the same genus have similar potentials within their uses) may help the issue. Also, I want to hit the point home that this comment is based on reading and background knowledge within biology. I have no direct experience trying to grow duckweed, but as it's been the hot topic within environmental and ecological studies I've read a fair amount about the plant at this point. Wishing you luck!

check NASA research they have been growing Duckweed for the international space station for years