Good brands independently list how much EPA and DHA are in each pill. Bad ones say "1000mg". That is useless, you can end up with minimal EPA and DHA and a bunch of filler oils. Meh.
Best I've found is ~600mg EPA and 400mg of DHA per capsule.
Edit: Good brands are purified, heavy metals should not be a concern.
Well be aware, 300mg of EPA means the value isn't quite as good as it may first appear. Multiply by 2.3 to get the dosage the same per $!
I have never used Swanson stuff before, typical worry about low cost fish oil is that it isn't filtered for heavy metals as well, and it may have a smell to it. Of course YMMV. :) I typically go to a local shop (more expensive of course!) and try out a brand there first, since I typically can return even the opened bottle if I feel something is wrong.
Good brands independently list how much EPA and DHA are in each pill. Bad ones say "1000mg". That is useless, you can end up with minimal EPA and DHA and a bunch of filler oils. Meh.
Best I've found is ~600mg EPA and 400mg of DHA per capsule.
Edit: Good brands are purified, heavy metals should not be a concern.