Well thats where the quality of the water comes into play, if you do not have plants and arent going to get any, then make sure you are using pure water like ro/di. I switched to good water and my slime algae receeded, as well as my hair algae. Also, reducing the amount of time your lights are on will help too. Make sure you dont have any spots in your tank that isnt getting any water circulation. (dead spots) As far as Diatom algae, my pods are eating mine and they are working on the green algae on the glass now..its amazing stuff