Bog/Veggie filters DIY quesiotns.

I'm damn sure I'm going to need more filtration for my pond. I have set
aside an area for this. It just so happens I had made the area while
designing the pond, so lucky me. The area is about 4-5"s deep. I can
elongate it with sand & pea rock if I have to too add the filter.
Do I have to have all the plants in containers, one big container all
together or plant them right in the pea/soil bed?
Can I just run a water line after the submersible filer/pump I already have
to the bog and control the water flow with a valve? The plumbing aspect of
ponding isn't really a problem for me seeing as that's what I do for a
living. its the balancing for the pond that's got me scathing my head. I
went to a wicked awesome nursery today & bought some plants for the bog
(grasses) and some more oxygenating plants for the bottom as well. So is
this a bog or a veggie filter? They the same thing more or less. Can someone
explain it to me like a 3 year old.
I could build a filer box as well but which method works best? If I do go
this route I'll use a flower pot as I want keep the pond as natural as
possible. I don't want to see plastic boxes everywhere. I don't want to use
chemicals if I DON'T HAVE TO either. I've been reading that DIY is a good
way to go. I take it the filter box should filter as slowly as possible
through the system without compensating water flow back to the pond.
Again thanks in advance for the input people.

--
The~Doofie~Man ©
"LET ME SEE YOUR CIGARETTE LIGHTERS!!!!!"
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