Had a hole in front yard where a stump was. Looked like the perfect place for a pond. Filled it with water a few times and put goldfish in. Survived two years. Now I lined it with a pool liner 18' x 2'. Added a submersible pump, made a small biofilter in a five gallon bucket, with lava rock. Put in some lily pads Hope all goes well. A couple of goldfish are surviving so far. Still need to finish edging. Will look to the group for advice.