I have used that more than anything else over the years with the addition of kelp and humic acid and sometimes a few other things.
Is it good or worth it? I have no idea, my trees live and grow is all I can say.
Yeah, a bit fishy, I've never noticed a smell after application but never used it heavily indoors either.
I just use it because it's an organic based product available on local shelves and some pot growers claim great results with it. A little goes a long way, doesn't seem all that pricey to me.