mystery killer?

[gav]

having some issues in my tank. thus far it has affected firemouths, angels, and now it is hitting one of my geos.

symptoms are usually i will approach the tank to feed, though it can happen other times as well, and a fish goes absolutely bananas. it swims around the tank erratically at high speed. then it just goes belly up not moving with all find hyper extended and the fish completely rigid. now sometimes the gills start working again, and in 5 mins the fish is back upright, 10 or so and it looks ok. i just cant work out what this is. no other symptoms i can see at all. pretty much all of the fish that have been affected by this have otherwise seemed to be in prime health.

so far have lost around 12 fish, and really dont want to lose too many more if possible. currently have the sick geo isolated in a float, but twice tonight she has had one of these fits, andi have pretty much written her off at this stage. just looking to try and stop others from meeting the same fate.

this isnt something i have seen in 25 odd years of keeping fish, so please bear that in mind with responses, its something rather unusual.

[Mr Wild]

I had a short in the heater once did something similar, its cheap and easy to change and it might be the prob!

[gav]

not the heater (wish it was that easy)

[Mr Wild]

Yeah Gav I knew it was a long shot but hey sometimes we forget the simple things. I suppose you have already done all the params - ammonia cab have then behaving like that. Could be parasites biting that will make them go mental sometimes too, if they are in high enough numbers they can cause a lot of bother.

Sorry can't help you anymore.

[Hollowman]

First things first, what are your water parameters? test results for Ammonia, Nitrite, Nitrate, Ph, temp, water change regime, feeding

Sounds like some sort of poisoning to me. :?

[gav]

ammonia and nitrite are both effectively 0, well cycled and stable tank. nitrates are also close to 0. dont get any appreciable result when testing for then, though there is always a little there.

water changes are every 4 weeks or so. low density population for the volume of water, so no real need to high volume changes. given its 1600L its also an attempt to save a little water. ph sits around 6, temp around 28 however i suspect KH is quite low. i dont have a test kit for this however.

feeding is either tetra colour bits, nls cichlid pellets daily and blood worms every week or so.

in terms of poisioning, is this likely when the fish is in its prime and having lost little or now condition?

[Hollowman]

Even though it might be a big water volume, changing water once a month is not good enough in my opinion and can lead to illness. I see you say that you have a cycled tank, if that were the case you should be showing at least 20-30ppm nitrate. It should not be near zero at all. Something is going wrong. How old are your test kits? might be worth testing with new.

What happens to all the uneaten food? do you clean it out or leave it to rot? Not much of a diet for the fish either, I think they need a more varied diet myself.

So, maybe retest the water with a new set of kits, up the water changes to 30% at least a week, and a more varied diet. I still think it could be poisoning due to lack of water changes.

See how it goes

H