you probably have a few things going on. Since the koi lived long enough to get a nasty infection, we can pretty well rule out parasites such as costia and ich since those can kill pretty quickly. I suspect a parasite was still responsible, possibly flukes. Flukes are irritating and cause a break in the skin. The bite gets infected, causing an ulcer. The fish is now sick, and a fungus called saprolegnia starts growing on the ulcer. Saprolegnia releases toxins into the fish making him even sicker. SAP alone can be deadly. I realize it is too late for this one, but in the future here's how I would treat that fish. Catch the fish and sedate. Gently scrub the wound with a q-tip and betadine. Remove all traces of fungus or it will grow back. Be sure to keep betadine out of the gills!! Treat the sore with a paste made of potassium permanganate (dangerous stuff....handle with care), or malachite green. Seal the wound with denture powder. With an ifection as bad as that one, I would also treat with an injectible antibiotic such as amikacin. The fish needs to be returned to a clean QT and the temperature needs to be slowly brought up from the pond temp to around 70°. A koi cannot heal in cold water. Further investigate the possibility of flukes on other fish. Symptons include flashing, jumping, excessive slime coat.

Susan I think chemicals are bad for your pond and I have been ponding for many years. I don't know what Microbe Life or GreenClean contain so I am not sure if they are harmful. But the best way to keep a pond healthy and happy is to keep if free from debris that settles on the bottom, filter the water and make sure it has lots of oxygen. If you don't want to add filtration the concentrate on debris removal and water changes. There are so many ways to filter your pond. Many people vacuum the pond bottom, some use retro-fit bottom drains to keep the bottom clean and those who are newly installing a pond will include a bottom drain to their ponds. Filtering the pond is important to keep maintenance at a minimun. You need to remove as much debris as possible with a good filter and make sure you have biological filtration as well. For example I have two circuits of filtration. My skimmer has a 57 watt UV light and all the water that is drawn from the surface goes to a big DIY filter that uses foam, plants and Savio springflow to help with the mechanical filtation and the biofiltration. My bottom drain goes to a settling pond in which the debris settles to the another small pond and it is cleaned out a few times a year. Since your pond is concrete then a retro-fit bottom drain could help. But vacuuming would work as well. When I first started out ponding I would vacuum my pond with a pump that I held with a small rope. I used that and a net to get out debis. Very low tech but worked well. I would then add fresh water to replace what I had taken out. Years go by and I have experimented with underground filters, Bead filters and DIY filters. When I rebuilt the pond (a few times I admit) the bottom drain attached to a seperate pond made maintenance much easier. So you just need to find the type of filtration that suits your needs. At the very least keep the bottom clean and do some water changes during the season. This is a very simple way to keep your pond healthy. Also the catfish will not hurt your fish. When I had my catfish he co-exsisted very well with the Koi. RIP Wayne. Lisa

I know our pond was discussed in detail on some koi forums, it was bought up by Roddy Conrad (many years ago) he discussed how we manage to successfully maintain clean and healthy pond practices with aggressive water exchanges and a separate biological pond. I read many of the posts with Roddy but unfortunately missed yours. Water changes and flow thru systems have of course been a cornerstone of fish keeping, from fish farms and hatcheries to backyard ponds forever. Many of the Japanese growers seem to have flow thru systems, but most of us don't have a stream/river in our back yards for that so we have to make due with water changes. Up until the last few years most of the discussion in Koi Ponds has been about how frequency relates to keeping fish alive. In the last few years it's changed by a very few people to frequency relating to other things like clear water. algae control, and increasing fish growth. It's new so interesting to me. What surprised me is that you are already basically doing the 24/7 drip thing except once a day instead of 24/7 and hose instead of drip. Your volume is right in the range of 10-70% per week (varies by goals). And you've been doing it for a really long time so that's good data. Not sure how long Andy Moo has been doing 24/7, he's been around a long time too. And of course you're also using your hose as a TPR and basically the same as vacuum. Whether dirt is pushed to suction or suction is moved to dirt the result is the same. And you're doing it often. Pretty much all the people I've dealt with who wanted a bottom system as a option (not required for fish load) wanted it solely as a convenience. They just want a pond for looking at fish after work and don't want to pick up a hose. I do not belong to any of these forums, ( I did try briefly, however they were beyond snobby) as they have very expensive Japanese koi and they have sterile ponds, (meaning no rocks on the edges) also their filtration systems cost many thousands of dollars and they are quite snobby about their koi and ponds. Hell they don't even consider butterfly koi to be koi. Every forum seems to have a single specific type of pond that the 20-40 dominating posters have. Every forum says they accept all kinds of ponds but that sure isn't true. They'll say "all ponds are different, and that's great" and then launch into telling people why their pond is all wrong. But that's forums, protecting their little world. I most read pond forums that sometimes have good info but I don't find much reason to post very often. I've learned a lot about that I might be able to adapt to other ponds and more importantly so I understand these systems. Aquarium forums are even better for learning but I never post in those since I've never even had an aquarium or are interested in one. But those folks sure know there stuff, lots of test data. I think the hard it is to keep fish alive the better the forum because they have to take everything more serious. Fish farming forums are good too. If it don't pay they don't use it. However, the main reason I won't frequent these koi forums is because with all their expensive and super elaborate filter systems -- many of them they still use PP to help clear their ponds. I don't get it, why subject your fish to dangerous chemicals? If you systems are so wonderful why do they need chemicals and uv lights? You can see the amount of trouble I could get myself into frequenting these forums. :) Besides, my koi are mutts. I haven't seen much in those forums about PP use for general maintenance in several years. Occasional use by few for a specific reason. Or maybe they just don't talk about it. There's been better filters developed since Roddy was talking about PP and way easier to use, and pretty cheap, oxidizers have become available since then too. They need those things because they keep a different kind of pond than you do. For example for me to do the kind of water changes in San Jose would have added about $80 per month to my water bill since they use a tried system. While $960 a year isn't a lot I kept the water clear enough for me using other cheaper means. It's just a choice thing. For my next pond I can design a pond specifically to include 24/7 drip so I can reuse the waste water for landscaping. Here in Phoenix we water the landscape all year, and use a lot of water for that. So the water from the 24/7 drip will be basically free. Free and completely automated me likes. I know Dr. Roddy Conrad from another forum that we were both members of. We got along well,( but I did disagree with his PP practices.) He knew our set-up that why he was able to explain to the koi forum members our set up and aggressive water exchanges. "Successful pond husbantry practices " he called it. I don't remember if the other forum members agreed with him. Probably not. The Doctor that lost all the koi in his pond (twice) was that from on overdose of PP? I don't think I've ever posted directly with Roddy but have reads hundreds of his posts. He may have taught me more about ponds than maybe anyone else, especially when I was first learning about koi keeping. I've just been interested in learning different techniques and don't really have an opinion on whether it's good or bad. Just a tool. A hammer is good for driving a nail, not good for opening eggs. The tool itself is neither good or bad to me. I don't find a lot applications for PP but when needed and useful it works fine. But I'm sure happy Roddy took the time to teach me how to use PP, it's effects, and it's downsides through his posts. I'd be happy to buy him dinner any day. Plus his explaining, experimenting and providing lots of early data on Trickle Towers was very important to the hobby imo. And he took a lot of crap from the peanut gallery to boot which taught me a lot about forums which has helped me in developing software. TT popularity may have been short lived in the Koi Pond world but lead to even better filters. So I take what I can from those forums and just try and stay out of the crap...as best I can.

Maxio, I hope you're getting your questions answered for you. I think Nance has done an excellent job of pulling together some background information to consider regarding your problem with what to do with the Koi pond water. Also, Gary and NancyM's suggestions are very helpful as well. Cityworm, rather than hijack this thread further away from it's original posting why don't you open a thread and present your case about what you view is the correct way to buffer the water and how you operate your Koi pond. I for one like to learn new things. I would be very interested in your point of view, the logic for your stance as well as whatever scientific basis you have for your practices. The beauty of this website is that folks share information. We may not always agree but hopefully we are able to educate and learn in the process. ---David