of as genuine grasses, rushes or that hair grass, genus Eliocharis?
Genuine grasses and a lot of pond plants need a lot of light. Many grasses will die if in water too long, however the "ponders" or pond people have discovered that barley or timothy hay, while rotting in a pond, produce something (An allelochemical?) which inhibits the algae. One can buy barley extract, but without heavy sunshine it seems unlikely to be much help inside except to acidify the water. (Guess who has a nice expensive bottle of barley extract!)
A number of house plants are rain forest plants from below the forest canopy. The yare "used" to less light and being in water. They will grow in filter boxes and other places where they can extend out of the water while "having their feet wet."
My Spathiphyllum (the plant which ate Park Forest and is working on upstate New York), Pothos and Phildendron do well this way. There are probably many others.
The underwater roots don't start as well from cuttings as land roots. So start the whole plant with the roots in water. The change will be amazing. (I root new water forms taking runners and sticking them in other tanks or a bowl. They will throw out roots.)
Also, if it is from a store, let it soak and grow by itself for a while. That should wash out any fertilizers or rooting hormones from the trade. Sometimes they can be found, very inexpensively at the end of a club auction, when everying is selling for 20 cents on the dollar anyway.
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