I hope I am not asking too much, but would appreciate some suggestions. We put in the attached reflection pond last season. No fish or extensive number of plants planned on. It has a flat bottom of stone with gravel seams between the flat bottom rocks. It is about two feet deep. Has a filter with UV, but not an ion generator or other filtration. Its intent is to offer a flat, reflective surface with no real motion intended. I want to add just a few plants to help with the algae control. If I were to add some irises (2-3) in front and against the tall boulder on the back side could they just be potted and sit on the floor two feet down? What variety? Will those few plants, the irises and two water lilies, be enough for algae control?