I've been having some serious problems with my koi pond and was searching the web for info/insights when I ran across this forum. This is exactly what I've been looking for and wish I'd found you folks last year as it would have possibly saved me from experiencing a devastating fatal experience with my koi at the end of last summer. I'll go into that in another post in the water chemistry section. I've been pretty much a fishaholic since my early childhood days, can still remember that first teeny tiny goldfish bowl with my first 2 comets. I'd watch 'em for hours on end and never get tired of it. Since then I've constantly had countless aquariums, tropical fish, etc. etc. etc. If there's any freshwater fish out there I've probably had it at one time or another. For some reason I never did get into the salt water area. I've also been an avid fisherman my entire life, concentrating now on flyfishing and flytying. About 10 -15 years ago for my birthday my wife bought me a small pond kit with the liner, pump, and all included. I built it in the backyard and although it was rather small, maybe 500 gal, I loved it. The next season I upgraded and built a 2nd pond about 2000 gal and got my first koi and became addicted to ponding. I was living in Calif at the time and believe it or not, I never once did any water testing whatsoever on either pond and never had problems with them. Did get green water but since our city water service was not hooked into a meter, I could change water at will and never worry about running up the bill. Fast forward, 15 yrs later....I'm am in a different marriage in a different state, Arkansas. Funny how life changes with time. Anyways we bought this 10 acre property in the country and it had a nice 15,000 gallon swimming pool included. One of my first big projects was having a 3/4 acre fishing pond dug out in the back, which is now stocked with 'trophy' Bluegill and some very nice Bass. I spend countless hours down there with my flyrod and home-tied flies harassing those fish. Don't worry, I've never killed one yet, always catch and release. Back to the swimming pool, after the first year we decided we didn't use the pool enough to justify the maintenance cost on it. So what does a fishaholic do with 15,000 gallons of empty water??? He puts fish in it of course. After my first two trouble free ponds in my Calif backyard, I figured the pool would be the same no hassle/ no problem kind of experience. I couldn't have been more wrong. After trials, failures, and much expense, I finally got the pond up and running very nice for 2 seasons and had about 40 koi in the 15"-20" range. Then towards the end of last summer everything crashed, my koi started dying, and I really didn't have the necessary experience and no how to deal with it. I tried a bunch of stuff, but in the end I lost all but one of my fish. I'm back this year with a new school of fish and facing the same problems but with new game plan. Hoping I can be more successful this time around. Anyways I'm glad I found this site and I've enjoyed reading the posts so far. Looking forward to reading and writing more in the future.