I have 2 litters of Tilapia fry/fingerlings ( not sure when they become fingerlings) that I have been raising in a 55 gallon aquarium, 1 litter for 2 months, 1 litter for 6 weeks. I'm thinking of combining the 2 into an IBC tote that I've been growing duckweed in and using as a drain/flow tank from my GB to my FT. I know the 2 month old litter can eat the duckweed but don't think the 6 week litter is ready for duckweed yet. I'm curious to see how long the duckweed lasts and how fast the fish grow with unlimited food. I know I'll need more grow bed area to accommodate this. Just looking for pros and cons to this idea.
Even fry will eat duckweed. They have to pick at it for a while, but will eat it all eventually. Fry and fingerlings also eat algae from tank surfaces. A nice green algae covered tank is nirvana to tilapia.
I fed my 2 week old fry a tablespoon of duckweed an hour ago. They have eaten about half and are still attacking it. The tank of two month old 1.5" to 2.5" fingerlings finished off a hand full of duckweed in an hour.
I still feed commercial food in addition to duckweed. I'm also going to try feeding chopped purslane in a month or so. It grows like a weed and has a high omega 3 oil content - high for plants. Will see how that works.
I did put them in the IBC and within a few days I had no duckweed left. I've always had a hard time growing duckweed.