goldfish pond/small water garden

Question
Hi, Brigitte,

We have a small kidney shaped water garden in our yard which heartily supported 2 goldfish (Frick and Frack) for over 5 years.  Late last summer, the water lettuce and water hyacinths got out of control within a few weeks, and coincidentally before I could clean it out, we lost F&F.

My husband, who has renal failure and dializes 3x week, really enjoys the pond and was literally devastated when the fish died.  We cleaned out the excess plants, and bought a dozen fry size fish at the pet store.  By spring we had six left. My husband was doing a partial water change and (diabetic so not the best vision!), had purchased a new container of water conditioner and thinks he read the inst. wrong and added too much chemical.  We lost the rest of the fish.  A week ago, we drained and cleaned the pond, which by this time was almost covered in string algae. We filled it, treated the water and put in a new pump and filter.  A few days later, I added three large goldfish which appeared very healthy. I bought them from a local bait store.  Two of them, I guess stressed from the new environment, literally jumped out of the pond.  I was able to get them back in, and they swam around and seemed ok.  Then, I began to notice them sluggish, not eating and observed a few small white spots on their fins.  One died that day, so I added some ick medicine and a little rock salt, hoping to intervene with the other two.  Yesterday, a second one died, and I was hopeful that these were the two that jumped out and had possibly gotten injuries.  Today, the third fish is sluggish and not gasping, but breathing hard.  I fear he is going to die too.  I've checked the water, and everything checks out safe, other than being slightly hard but within the safe zone.  I can't figure out what else could be wrong.  I've had fish and water gardens for years and have never had this kind of problem.  I'm wondering if it was a combination of things, and that maybe I could add 2-3 more fish now and with everything settled down, it would be ok.  However, if I've missed something, I would appreciate information you could share.  Thanks in advance for your comments.

Esther & Jack

Answer
Hello Esther and Jack!
It sounds like you are doing everything right.
I must tell you that Goldfish that are sold as bait often already have some sort of problem...that is why they are being sold as bait (they are not much good for anything else).
Your best bet is to get some fish from a reputable pet or pond store.
Take some pond water with you for additional testing, just to make sure.
I would treat the pond a couple more times for Ick to catch all the bugs and their unhatched offspring before adding new fish.
Make sure you have lots of aeration and make sure the salt level in the pond is at the optimum level for fish and plants. In addition to aiding the immune reactions of the fish, the salt also helps to relieve the stress from moving to a different environment. Make absolutely sure the salt does not contain any harmful additives!!
Do not feed the new fish for a few days after adding them to the pond (this will let the beneficial bacteria colony catch up to the increased waste level).
Hopefully this gets the pond back to being a pleasure!
Brigitte
www.pondmarket.com