[hoppycalif]

I would definitely leave it alone. The amount of plant matter that will decay is so small I can't see it harming anything. And, the plants will appreciate the chance to continue undisturbed.

 

[hoppycalif]

It seems to be accepted opinion that Marsilea minuta will grow much better with low light than the other carpet type plants will. I'm not sure what the lower limit on light for that plant is.