Hi, ive made lots of fish stock before so know to simmer it only very slowly and for about half an hour. This one included fish bones, heads (no gills) and a bit of skin and the odd scale from 5 UK south coast pollack (plus various finely cut veg).
It has finished a murky colour somewhere between brown / grey / green, which ive never seen before as it would normally be a much lighter colour. Is this normal / somehow linked to pigmentation in the pollack's skin or similar?
Ive never made a stock from so many pollack before (normally a mix of other fish) so is it something in their pigmentation?
Any help or reassurance appreciated - im not really worried about it as i know the fish was fresh but am keen to understand and google isnt helping me!