I got some duckweed recently - was going to feed it to my goldfish. It looked like a small amount but once I put it in a bowl I realized there was a ton of it. I was going to feed a bit at a time to the piggies in my 90 gallon. So I put it in a big white mixing bowl (about 2 or 3 gallon) and put on a shelf near the sliding glass door where it would get lots of sunlight. Within two weeks it was all dead.
What did I do wrong? Does duckweed need a current to stay happy or should I add ammonia? I'd love to have a never ending supply of the stuff. The goldfish would eat it all before any grew.
duckweed would feed on nitrates in the water which probably wouldn't be present in your mixing bowl. Adding ammonia would only help if you had a cycled filter in there as well. Try taking old tank water every 2 or 3 days and replace the water in your bowl.
Another thought would be to get a floating breeder trap, put it in the 90gal with the duckweed in it. It should get all the nitrates it wants and will keep the goldfish from eating it all at once. The only drawback I see would be that a breeding trap wouldn't hold very much DW.
Makes sense : ) Good idea on the breeder trap I have a couple and will try it out.
Thanks!
one last thought would be to just add plant food to the bowl once a week.
I warned you there was lots in the bucket ;)