I know it sounds counter intuitive, but would it help to switch back to a feed that uses fish meal as the protein source? I never had this problem when using Green Mountain Organics or New Country Organics. I believe they both use fish meal. Now that I use a feed that uses canola and flax instead of fish meal I have fishy eggs.
Ya, seems odd doesn’t it? You’d think feeding fishmeal would cause issues with fishy smelling eggs, but it doesn’t. I wish I had a better solution for you!
You basically have three choices at this point-
1- Go back to feeding a soy-free feed that has fishmeal in it, and significantly less flax and/or canola.
2- Feed a soy based feed.
3- Swap your chickens for the more popular/commercial breeds, that have that trait bred out of them.