[chriss]

OK, slightly different fishy topic... koi fish and why can't I keep them in my pond, they keep dying, whilst others survive fine.

Our pond holds around 800 gallons plus a 50 gallon filter tank, it's been up and running for ten or more years. Admittedly, the only maintenance it gets is the sludge cleaned out of the filter, the bottom cleaned once a year, if it needs it. Water change wise, well it gets all the RO waste which causes it to overflow so it gets plenty of fresh water. It's in a shady part of the garden and is always cold, too cold to put your leg in for more than a fleeting moment. I have never tested the water for anything.

For the last few years we haven't added any fish, leaving us with a couple of large koi ( ~14") and 4 or 5 large goldfish of sorts. This year we decided to add a few more to it, so added a selection of koi, shubunkins, sarsa comets and some other random pond fish, all in the 3" range from a nearby garden centre and an lfs in Camborne. All but one of the koi's have perished, whilst the other new additions have done fine. They perish over a week or two, sometimes we find the remains other times not.

Are they just poor quality fish being sold cheaply with the attraction that they are 'koi' or are they significantly more delicate or what?

Chris

(Off-topic pi$$ taking posts will be dealt with severely )

[karnivor]

Any signs from them, like flashing, jumping, sores etc?
Yes, you can get some pretty dire Koi if they are bought from some suppliers.
Gill flukes are very common on koi that have been UK bred and not properly treated before shipping.
japanese and israeli koi are usually pretty good.

[chriss]

karnivor, on Jun 21 2010, 04:59 PM, said:

Any signs from them, like flashing, jumping, sores etc?
Yes, you can get some pretty dire Koi if they are bought from some suppliers.
Gill flukes are very common on koi that have been UK bred and not properly treated before shipping.
japanese and israeli koi are usually pretty good.

We never saw them jump and those bodies that we have fished out have never looked obviously diseased. As for the source, no idea. At the garden centre they have now labelled some of the koi tanks with a particular 'brand' stating their high quality, but they were larger fish than these which came from tanks which are un-branded.

Perhaps I should try some larger specimens or find a more specialised supplier.

Thanks

Chris

[Marcus Watts]

hi Chris,
check the ph m8, and is the water still clear - even with the very very enriched water from the ro unit? the normal goldfish species are virtually bulletproof, surviving the widest ranges of water conditions you could create, but the koi are a little more sensitive. I used to breed and rear a few 100 thousand koi a year in an indoor hatchery with biofilters larger than the tank volumes, and then we used to move them into ponds under a polytunnel. They are basically carp but genetically weaker so they do like good water, decent O2 and low pollution,and its highly likely the shop ones will have come from Israel so will be used to nice warm temperatures, (although they may be labelled as Japanese, just like indo corals with aussy labels haha). Japenese koi are very slim, very bright and relatively expensive £20.00 + for 3", and most of the tank of fish will appear white and deep dark orange with really sharp borders between the colours. The japanese cull 90% of the littluns to preserve the colour and bodyshape qualities where as the europeans try and keep 90%+ alive to make the most profit. Cuddra aquatics is a very good local koi keeper (st austell) but the best retail stock i've seen in the uk, and one of the best setups i've been to, is Koi water barn in orpington, Kent - they have a web site worth a look i think

cheers marcus

[chriss]

Thanks marcus. A bucket test shows it barely greener than my reef tank water on change day so that's pretty good. Although it is ro waste, my unit is pretty wasteful, but source Tds isn't horrific so guess that helps. A ph test using my digital came out at 7.0 bang on, could be softer?

What sort of temperatures could be problematic as the pond is always cold?

Price range is usually around a fiver, maybe that is indicative of the quality of the fish.

Chris

[Marcus Watts]

chriss, on Jun 21 2010, 08:39 PM, said:

Thanks marcus. A bucket test shows it barely greener than my reef tank water on change day so that's pretty good. Although it is ro waste, my unit is pretty wasteful, but source Tds isn't horrific so guess that helps. A ph test using my digital came out at 7.0 bang on, could be softer?

What sort of temperatures could be problematic as the pond is always cold?

Price range is usually around a fiver, maybe that is indicative of the quality of the fish.

Chris

good evening m8,
the water sounds fine for concentrations of algae etc and ph perfect. Being carp they like to break true winter dormancy and 'wake up' at about 15-16 deg. they will shed spawn or spawn successfully after 3-4 days of temps over 20 deg. Even though its in the shade the weathermen take their temps in the shade so it should bet into mid teens most summer days. Unfortunately many imported koi have no true developed imune system to the day to day bugs and diseases in the uk pond so they tend to keel over sooner rather than later.

UK bred fish do much better if you just want some nice colour and hardy fish- lanivery carp at lanivet were good for these if they are still going, but tbo i wouldnt go to the expense of high quality jap imports mixed in with standard goldfish based stock, - back to the imune system problem. One 6" fish will have a much better chance than 4 little £5 ones too - it will have overwintered once and built up far more resistance to lifes little problems

[tommo]

just sounds like they aren't being dealt with properly on import. Unless the fish have severe viruses which is, i suppose, possible considering the short time in which they keel over- it could now be latent in the goldfish- then they are dead easy to restore to 100% healthy and well catered for prove extremely hardy long term. Quarantine and settling in an appropriate environment is as important as good turnover to make sure that the fish that are sold are in top nick and giving maximum profit overall. Thats why we import good quality magnoy isrealis, hold them until we have got them clean and packing weight on we feed them top quality diets, and then sell them cheaply- but in volumes. Good business sense, and backed up by one of the most effective, well designed and complete pond systems you could want. We dont get repeats of problems whilst the fish are in once settled, and we dont get complaints. we do however get alot of people returning for more fish - often along with a bigger pond (year on year) and we have no excess stock at the end of the season except for one or two big ones which keep the system ticking over for us

All about good management.

Tom