Roots in the Water Column

All right, at first it was fun to watch. Now it is becoming an unsightly
mess. All of the stem plants are growing roots in the water column outside
the substrate. Is this something I have to learn to admire, or is there
something that needs to be done I'm not doing?



The ludwigia repens is doing so well, the leaves are a gorgeous mahogany
brown. But the roots it has grown outside the substrate are so thick; they
are ruining its look