I HAVE THIS ISSUE KIND OF! They (my 2 gouramis) tug hard at exposed roots, and algae, sometimes uprooting my wisteria. They will nibble at floating leaves too. They mostly eat algae, unless its feeding time and their are flakes, pellets, etc. in the water to feed upon. These fish are colorful, freshwater, eating machines, and pooping machines.
Let the plants float a bit. The tank will still get cycled... and these fish don't belong ina non-cycled tank. I suggest adding more gravel/dirt, and place a lil more weight around the roots to help them from being uprooted.
BTW, my large Mystery Snail, uproots more plants, running around, than do my gouramis! My snail barrel rools over plants, looking for dead leaves, but leaving the green stuff alone. He has uprooted Java Fern many a time (but I don't mind free floating Java Fern once in a while!)
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