Question
Recently had to rebuilt pond due to leak, put fish(koi & goldfish) back in with declor and fish have been trying to jump out of pond.  Lost 1 koi and have now put net over pond.  HELP

Answer
How big is the pond? Was this a 100% water change?  Is the pond clear of debris (cleaned out while rebuilding?)? How long after the change did you put them back?  Is the pond well aerated?  Did you test the pH and hardness to see how they compare to what they used to be.  Sudden changes can stress the fish.  Jumping tends to happen when the water quality is irritating them.  It could be from chlorine (but you used dechlorinator), low oxygen, pH changes, poisons (what did you use to rebuild the pond and fix the leak as far as chemicals goes?), and parasites (not likely in this case since it seems to be related to the new water).  I would test your water if you haven't and aerate it really well.  I hope you can figure out why they are so stressed.  If the pond has a lot fewer plants and things it, that can also scare them but shouldn't really make them try to strand themselves.

Robyn
fishpondinfo.com