Hello. Just thought I would share my experience with my guppy pond. I have had a medium (1000 gal) gold fish pond for a few years with good success. Got a slight case of Guppy fever and thought would be fun to set up a small outdoor guppy pond. I have a old farm watering trough (gavanised steal) that I have dragged around for years. It is around 120 gal. I put the trough in partial shade, filled and put a dwaph water lily, few cat tails and couple other water plants (plants are all potted). Trough is bare bottom to assist with cleaning. Added a few empty pots to give the fish a little more cover. Perform a water changes ever other week (use a 5 gal bucket, take 3 or 4 bucket full of water out at a time). Use the garden hose to refill (well water). Added two breeding pair of guppies. Try to feed daily, but comes out more like 5 times a week. Feeding dried flacks...assume their are bugs and such in the water being outside to balance out their diet. Guppys in pond are much more active then ones inside in my aquarium. My two males are white with red tails (easy to see in water), females are more gray (much harder to see). It been about a month and fish are healthy. Saw a fry the other day so thinking water quality is good. Hope to have some good fish to harvest this fall. Will try to post a few pictures of the pond and guppies I get this year from it.