Heck, you can go out and collect kelp and dry it yourself.
You could look at the BIOBIZ line of nutes too, they are organic.
Their nitrogen base is basically a fish emulsion.
If you are doing soil, learn to steap 24 hour earthworm casting tea, and only feed that to your plants.
Thanks. I will look into making that tea. is it possible for me to also add some kelp, dried fish bones to the same tea? I also have chicken, cow, goat manure.