hi this is my first time with the hidro its more (pot) look soz about that.ther is a bit of algee .the plants dont minde.the water comeing out is the start of the cical ebb&flow.foil on the walls well its some think i red. its winter hear we get bad frosts uk.so thats not a problem.will use mat pante next time if u look closer u will se the tray is full of water. thanks