Randy R wrote in message
oups.com...
What a lot of people do is put plants in the smaller pond for a sort of
bio-filter and to promote oxygen (this is referred to as a bog.)

Well, it's not necessarily a "bog".
What it is is a veggie filter. Fill it with lots of plants
Water Hyacinth are best, cilantro from the grocery store will work
good too. No fish in the small upper pond, after a week or so get
some feeder goldfish from the pet store, .12 - .15 cents each.
If they die you're not out much. Have fun.

Ron