Sorry for the delay in my reply. I wasn't watching this thread. Umaxx contains a urease enzyme inhibitor and dicyandiamide a nitrification bacterium inhibitor. Holganix advised me not to use these types of products with theirs. Holganix adds bacteria to the soil and encourages microbial activity and anything that would decrease bacterial activity should not be used. They believe that other bacteria may be inhibited by the dicyandiamide as well so they want to leave it out.