Question about Flux leftover when Pouring

Newbie here, 3rd pour of this 2.05ozt sterling ingot that used to be a candlestick and some scrap jewelry. Pickled with a salt & vinegar recipe I saw online and quenched in baking soda and water, still big chunks of borax flux on the surface. Am I using too much flux? How should I go about removing it from the ingot? TYIA