Oh man what a loaded question, feminized seeds are made from female plants only so yes. But no what you will produce will have a roughly 25% chance of not being hermie let's do this together
When you breed you get
1. Like mom
2. Like dad
3. a mix of the two
4. showing earlier traits, can be from anywhere in the gene pool
So since your plant obviously was hermie (a female plant which pollinates herself) here's your dice rolls on your seeds from the numbers above
1. Like mommy, she's a hermie
2. Like daddy, mommy is daddie, so a hermie
3. A mix of the two, oh crap this is a hermie plant
4. Here's your wild card seed
Now something in the back of my head keeps screaming it isn't 25% it is 12.5 % chance, I might be missing a piece of math.
P.S. Can't give you any advice on Ocean forest soil per your rules, I have never used it..