After using for a period of time, the effect on sps is quite obvious, colour become more intense and brown sps also coloured up.
Rather then dosing once a week, I dose A on first day, B on second day and C on third day and repeat. I also turn off the skimmer for a period of time for better absorption.
During that period I also dose poly roid, can see sps feed poly.
Best part the price is good.