Foaming stuff growing with my Duckweek...

[Josiah Sherman]

For 7 months I have been growing ducking and it has been growing good. About a month ago some foaming starting growing with it. I'm not sure what it is, but it seems to keep the duckweed from growing very fast. :-(

I'll include some pictures I would appreciate any advice.

Thanks,

Josiah

[Albertus W]

i've encounter this once when i put too much rabbit manure into the water. vacuum or throw away as much manure in the bottom  as possible & dump all the water. start with fresh one.

[Jon Parr]

The foam is probably algae, and I'm not sure what to do about it. My guess is the water is too warm, or too rich, or too stagnant, but just a guess there. I get small patches of it late in the summer, and I grab those clumps first to feed the fish.

I agree with Albertus, probably best to start over, and keep in mind that duck weed prefers ammonia over nitrate.

[Dawn Owens]

I'm pretty sure it's protein foam (the same foam you see at the ocean beaches after the waves come and go); it's simply a byproduct of the fish in the system; the green color is algae that's feeding on it.  You can net it out with a fine net swirled in a figure of eight fashion across the water surface, rinse it with a garden hose and return the duckweed to the tank.  You may be feeding the fish too heavily for the current water temp, or simply need to increase the water turnover rate per hour through your system. THERE'S NO NEED TO DUMP ALL YOUR WATER! 

Why are people putting rabbit manure into a system?  Seems like a great way to increase contamination issues.  

[Josiah Sherman]

Thanks for all the advice!

I have rinsed the duckweed and it seem to be growing much better.