Thinking about setting up a pond....

Smallish. I'd like to see the fish and give them room to swim in so it'll be fairly wide and 8" deep at the shallowest part, but I'm going to give them atleast a 2' (radius) circle with a depth of 3' and a with an accompanying heater to keep them warm during the winter.

I'm still unsure what a bog filter/garden is.
 
A bog garden is a wet spot but not flooded that constantly has moist soils and grows marginal/bog plants like Arrow arum and purple flag iris.
 
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