How much duckweed is required to start a colony? I have about 4 little leaves that came with my recent shrimp order. Will they start a colony in a heavily lighted and well manicured tank?
It kinda depends on your surface agitation & filtration...too much of either can spell doom to this (less?) than desirable plant. My husband would like it in some tanks but it's always in higher flow or really good filtration without prefilters...the tank I don't like it in is my "riverish" tank with too many surface leaves (jungle val) but lots of flow...but then, I don't have it in any others AFAIK (fingers crossed). Try frogbit or something less problematic. Filters in duckweed tanks need more cleaning, there's more "stuff" to rinse/remove.
duckweed is pernicious, invasive, intrusive, obnoxious, and a plant OF THE DEVIL!!!
seriously, see above comments. If you have four today you will have 27 in a week and the tank will be covered an inch deep shortly thereafter. It is alleged that turtles, and some goldfish, eat the stuff; I find this improbable since if it were so the world would be covered in turtles and goldfish to the exclusion of all other life forms.
shun it. Ban it. Dust off and nuke it from orbit, it's the only way to be sure. OF THE DEVIL, I tell you.
Duckweed is very efficient at removing toxins from the water such as ammonia and heavy metals. It can grow very rabid in water that is undesirable for fish. It will oxygenate the water much better than submerged plant growth, and makes use of atmospheric carbon rather than competing with the other plants in the tank. Its growth at the surface will offer shade to fish.
I find it improbable that the world would be covered in goldfish.:22_yikes: