i have normal skimmer and have resolved the problem by putting the wavemaker near to the sand (1), ensure reduction of nitrate and phos by introducing additives. Some pple told me red slime dervies due to high nitrate, some say high phos, i dont know and just buy both additives. Things start to get better. I didnt reduce the time of the lightings though.
I heard that there is a product call slime away to remove slime effectively. But that is not a long term solution and i didnt try that.