Ellie asked about cod liver oil. I find that it gives a clear signal about
whether it is "needed". If it smells unpleasantly fishy, I don't have a
tablespoon or so. Otherwise I do. Same for Melisa, though she tests it
(several times a week) more often than I do (once or twice a week). I
wouldn't trust it to provide a taste-change though.

TwinLabs plain (Dale Alexander's brand) is the best I can find, but there
are unanswered questions about it to my mind: Is it from farmed salmon? Are
the accumulated toxins/pollutants more problematic than the EPA etc is
beneficial?

Still, when we have no fatty fish for a while, I can tell that the cod
liver oil is bridging the gap...

We get the smallest bottle available. The first half always tastes better
than the last half and we tend to throw it out when it starts to oxidize
(as eveidenced by smell). YMMV.

Cheers,
Kirt