I use many Seachem products, but haven't used these in particular. I don't often find I need chemicals of any kind in my tanks if I am diligent with weekly, sizable water changes (25-50%). Also, every tank I have ever owned went through a diatom stage when they were between 4-9 months old. For me these always begin to disappear after that on their own. I have not kept otos, but have BN plecos in many tanks, but they never seem to address the diatoms, rather other types of algae. Still, I think keeping up with water changes and cleaning the glass manually and eventually diatoms seem to go away after a period of time on their own.