As above, diatoms are pretty much inevitable with most new systems and any fresh sand added. (you'll even get short bouts when adding sand to a well established set up alot of the time). Silicates are the driving force behind thier ultimate survival, which they use to build the cell wall structure. As long as you arnt adding more by way of poor quality water (hence the common recommendation for RO/DI) then they should use up the reserves in the tank and what came in with the sand within a few weeks.
Even mild cyanobacteria blooms i wouldnt worry about too much, as these are quite common as well early on.
You could stir the sand to break them apart but to be honest I wouldnt bother as most of it will just settle out again, plus you'll just be disturbing the sand layer at a time when its trying to settle and stabalise (thats if you are intending running a shallow live bed, rather than a cosmetic one thats syphoned).
Generally I'd just sit back and relax. Tanks commonly go through several cycles in the first 6-12 months. The better the water quality (low free nutrient pool) the quicker and less invasive these cycles will be. Alot of the time, interfering just stretches out the process even longer imo.
Regards
Simon.