The best way to treat cyanobacteria, commonly known as red slime algae, involves a multi-step approach that includes:

1. Physical Removal: Siphon off the cyanobacteria from the aquarium surfaces.
2. Water Changes: Increase the frequency of water changes using RO/DI water to reduce nutrients that cyanobacteria thrive on.
3. Nutrient Control: Maintain balanced nutrients in the water, aiming for phosphate levels below 0.10 ppm and nitrate levels below 5 ppm.
4. Lighting Adjustment: Limit or change out lighting to discourage cyanobacteria growth.
5. Feeding Schedule: Modify the tank feeding schedule to prevent overfeeding and excess nutrients.
6. Aeration: Increase aeration in the tank to improve water circulation and oxygen levels.
7. Filtration: Enhance mechanical filtration to remove organic compounds from the water.
8. Beneficial Bacteria: Add beneficial bacteria to outcompete cyanobacteria for resources.
9. Chemical Treatments: Use products like Chemiclean carefully, following the instructions, to target cyanobacteria without harming other tank inhabitants.