1. Manually remove as much as possible (siphoning/vacumming)
2. Increase water change frequency
3. Replace Bulbs in lighting system (if aged)
4. Run Carbon
5. Run GFO (phosphate remover)
6. Switch from tap water to RO/DI
7. If you have RO/DI already, check TDS of water and replace filter elements if necessary
8. Reduce feeding frequency
9. Change filter pads/socks more frequently
If you can tackle most of these above methods, you should see a reduction in the cyano. It will be a battle, so be prepared. Also, once you've implemented these action plans (only once you've performed these things), shut off the tank lights for a couple days to really provide the final nail in the coffin. But be patient, it may take a while
