It sounds like it's an environmental thing. Is is possible to take all the fish out and into a tank? This might be the best way to treat them. I'd then give the pond a thorough clean out and filling again with fresh dechlorinated water.
Obviously the tank has to be decent size and filtered otherwise they'll be more problems. Use ammolock (or similar) as well. Once the ponds cleaned out and refilled, leave for a week or so and put the fish back.
marko wrote: When I filled the pond with tap water I didn;t use any dechloronator as I planned to leave the pond for a few months before stocking anyfish. My local aquarium told me this would be OK as the chlorine will have evaporated, however I have had to top up the pond with tap water directly a couple of times becasue of evaporation and losses.
However thinking about it 4 weeks ago I had to fill up approx 25% of the ponds volume with tap water as my fountain developed a fault and sprayed my pond water onto my flower beds thus empting the pond to the level of the fountian pump, which luckliy happens to be approx 8 inches under the surface.
Is it possible that becasue I used tap water to top up the pond I have somehow casued this problem by weakening the fishes immune systems?
I haven't added anything to the pond for atleast 4 months, the last fish to join the pond was one of ths shubunkins and also has a unlcer on its back, but this fish was the second to last fish to devlop a problem.
Regarding the ph addative my local aquarium sold me it by Interpet and is called ph adjuster for alkaline ponds. I've only added one dose to the water so far, according to the instructions I should add 2 more does in the next 2 days. Should I stop adding this to the water?
OK, you need some dechloronator. When you filled the pond, there was no bacteria in the filter which is fine (the lfs was right - for once ), but over the weeks, there would have been a build up of bacteria in the filter. Using untreated tapwater kills bacteria - including the good guys. Each time you add untreated water to the pond, you're starting the cycle all over again and your fish have to go through it with the filter. This could actually be the cause of the fish's illnesses.
Secondly, ph adjusters cause the pH to swing, which causes more harm than good. Most fish can adapt to the pH of their water - especially if it's similar to the pH of the lfs or breeder's water. I think fish can cope with a 2 degree pH difference per day, but don't take that as Gospel - hopefully someone more in the know will come along and help with that one. Any more than they can take, and it stresses them out.
beeky wrote: Obviously the tank has to be decent size and filtered otherwise they'll be more problems. Use ammolock (or similar) as well. Once the ponds cleaned out and refilled, leave for a week or so and put the fish back.
Ammolock will screw up his water readings The ammonia level is fine atm.
Thanks for all the replies, moving to the fish into a tempoary tank and cleaning the pond out was something the crossed my mind but I don't really have the faciites to put my fish into tempoary accomodation at the moment so it's really something I 'll do if its the only thing left to try.
If this is the only route left can anybody advise me on where I can get a suitable holding tank. Would it be possible to use something like a cheap paddling pool from ASDA or would this potentially cause more problems if the plastic material contaminates the water?
Also I only have one pump and filter, would it be acceptible to clean out my current pump / filter and then use this on the tempoary tank, or would I need to buy an new one too?
it looks really nasty (sorry - great technical expert view there) anything made of food grade plastic will be ok to keep fish in if you could get anything big enough, or is it possible that a local koi place could lend you one of their big blue plastic holding tank things? sounds from your water readings as though filter bacteria are coping ok despite addition of tap water - but why is pH so high, what is your tap water reading, have you got any limestone rock or anything in pond? sorry not to be more help, ponds not my area ...