In ULNS (Ultra Low Nutrient Systems) aquariums corals can have poor colouration and unhealthy if they are starved of available phosphate. Coral Essentials recommends using Coral Power Phosphate Up when you can not achieve the levels of phosphate to maintain a balanced carbon/nitrate/phosphate system. Coral will be more vibrant and colourful when nitrate and phosphate are maintained at correct levels. Coral Essentials recommends running your aquarium at a phosphate level between 0.01ppm and 0.05ppm.
Manual Dosing
Only for ULNS systems we recommend starting off dosing 1 drop (0.05ml)/day for each 100L (26 gals) of tank water. Variances above and below the recommended dosing can be made depending on your own tank conditions and density of coral present.
Advanced Dosing
For the advanced aquarist 1ml will raise the phosphate levels by 0.01ppm (mg/L) for each 100L (26 gals) of tank water. For drop dosing, 2 drops (0.1ml) will raise the phospate levels by 0.001ppm in 100L. If you know the PO4 depletion rate in your system then dose accordingly as per above.