Except I have never had lotus in this tank so unless the lotus was mixed in to the swords root system I am not sure how thats the case. The stems in question seem to be coming up as part of the sword plant as well and the leaves of both are almost identical. There are four swords in close proximity if that is why you came to that conclusion.
The work will wait while you show a child a rainbow,
but the rainbow wont wait while you do the work