Bergman Roof Cleaning Report post Posted February 16, 2020 I bid all my roofs in person. If a roof is bad enough, I use Hang Tight - or similar- If it's really bad, On an average roof, I use only Gain 44 ounces to 100 gal tank. WHY? Additives to increase dwell time etc, also increase plant "Cling" So, half my roofs are done with about a 45% - 50% mix. My local chlorine is only 10.5 %, so I end up with about a 4.5 to 5% mix and with a ground man watering, I haven't killed a plant in over 3 years now. :-) Share this post Link to post Share on other sites
