So the cycle is complete and you have a new set of lights. Very common to see this happen. Other algae blooms may come and go over the next few weeks. Unless you have corals then you can simply run your lights at a reduced photo period for a while and work up to a normal schedule of 8-10 hours. So start with 6 hours and add a half hour each week. This may help with some of the algae blooms. The diatoms will dis appear after they exhaust the silicates in the water column.
Thomas