You should remove the bulk of the Pistia stratiotes from center leaving only a small grouping on each end. This will allow 'much' needed light into pool for 'much' needed aquatic plants. Bear in mind P. stratiotes is terribly invasive in natural waterways and illegal in many regions.
— Cory Nudelman
The scape and layout is effective and the selection of plants in the background are appropriate. However I think the plants in the foreground throw off the sense of scale because of how large the leaves are.