Bog garden

I am planning on setting up a bog garden this summer and have a question
in ref. to liners. After doing some reading I noticed that some people
recommend digging the whole and lining it up with a cheap liner, then
making holes in the bottom for slow drainage. I plan on eventually
building a pond for fish alongside the bog garden. The bog garden I
plan to use as a filter. Size of bog ~10'W x 20'L x 18"D

1. I plan on using a good quality liner with some type of pvc piping at
the bottom to help distribute the incoming water from the future pond.
I want to use this pipe system to help me partially drain the bog for
the winter. Is it a good idea to drain the bog?

2. If I do not poke holes in the bottom of the liner, will the bog
garden begin to putrefy? THe bog garden will probably stand alone for a
couple of years until I get time to build my pond.

Thank you in advance for any assistance.