effect how much aglae is made e.g if i fill my tank all the way up 2 cm from light will aglae grow better/worse than if its say 5 cm away. The algae on my light is annoying as it makes my tank really dark.
It'll grow no matter how close or far the water line is. The best way to manage it is to keep the lid as clean and dry as possible and reduce the amount of light in the tank.