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My fiancee did a water change on our 72 gallon bow front, he did a large one, cause it was time for a good gravel cleaning. He removed the parrots so he could lower teh water level enough. Well after he filled the tank back up, using some stress/dechlorinator, 2 out of our 3 pictus cats, seemed to have gone into instant shock and died. We have NEVER had a problem like this before and are extremely confused and upset. We tested the water paramaters, nitrites were 0, no ammonia and the ph is 7.8, which is normal for our water, and our fish are used to that. We honestly can't think of why this happened, and why the deaths were so fast and sudden. We thought that perhaps we had to snap some of the driftwood to get it to fit a certain way, but we don't think that should have been an influence. Can you help deciper this mess?

72 gallon bowfront:Tanganyikan Lake set up
75 gallon: A. Baenschi trio,Cyanotilapia Afra Cobwe(4), copadichromis trewavase, protomelas sp. tangerine tiger(breeding pair)

What were the nitrates in the tank before the water change? Catfish in general tend to be sensitive to nitrates, so if the nitrates were high but then significantly lowered by the water change, it could have induced shcok.

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I'm not your neighbor, you Bakersfield trash.

"2 out of our 3 pictus cats, seemed to have gone into instant shock and died." -

Only 3 causes that would cause instant shock and death in this case..

1. TEMPERATURE SHOCK. Perhaps the water going into the tank may have been colder then the water going out.

Pictus would be especially sensitive to a chill, and large water changes. All is takes is a more then 2 degree difference in temp. For sensitive fish, water should be aged to de-gass the water and let the conditioner neautralize the chlorine/chloramine/heavy metals BEFORE it goes in the tank... (leads to #3)

2. HEART ATTACK - a large noise and vibration suddenly echoing in your brain could cause a heart attack from shock also. Such as snapping driftwood inside the tank..

3. Poisoning/osmotic shock - doubt this was the case. More fish would have died or be sick right now. The next 24 hours will tell if your water supply has anything funny in it.

In either way, I'm sorry for your loss. Pictus are really nice catfish. Hopefully you'll replace at least one to keep the first one company.

*quarantine it before putting in tank* - new pictus arrivals famous for 'ick'.











Last edited by DaFishMan at 13-Sep-2005 20:35

The Amazon Nut...

Could your ph have crashed? If it had been a while since you last did a large water change the ph could have lowered quite a bit. If the water you put in had a high ph, the shock could have done the cats in.

A large water change (50% or more) every week prevents drastic changes in ph because the ph doesn't have time too change too much. It is always close to the ph of your tap.

Could have been temp as mentioned and that's most likely if no other fish show ongoing signs of distress but ph is something you can test for. Now if you still have some of the old water and in the future if you have gone a long time between changes. Do it before you change the water and if the ph is more than .2 different from your tap do small changes over a couple days to bring it back up.

Mike

If you have tested the ph in the past month and it matches now that shouldn't be a problem. If it's been several months then the ph in the tank could have changed slowly over time. A high change in nitrates or temperature is also a very likely cause. Another could be a change in the way your city filters the water. Sometimes they decided to add something do to an extra bit of bacteria in the water or for various other reasons. Sometimes if a water source is running low they'll draw water from somewhere else that could be completely different from the old water. That's one reason I use ro water. It's always the same unless I screw up my measurements.
It's better to change around 25-30% frequently instead of 50% or more infrequently because the tank water will slowly change over time so the parameters no longer match. Also if you change a smaller amount and something has changed in your tapwater then it's less likely to do harm or at least not cause a death before you notice something is wrong.

Last edited by sham at 13-Sep-2005 22:36

I agree with what Cory Addict posted, if they where used to the nitrates & all of a sudden they whered lowered, it could have caused he deaths. I'm sorry for your loss & next time do regular water changes & not a big one, over a long time.



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There is always something to learn in here !

But I still question if a large nitrate reduction or ph change would cause INSTANT DEATH. Has this happened to anyone else ? I would think that kinda death would be over a slightly longer period of time ? These 2 things never happened to me so I can't speculate although once I put minnows from the lake into the oscar tank and due to the 6 degree temp difference they all went into shock spasms and half of them died the instant they hit the tankwater, less work for the oscar..

The Amazon Nut...

When I change the water in my tank, I lower the temperature of the tank about five degrees by adding cooler water, to simulate a rain shower. Fish are exposed to drastic water temperature changes in the wild, from day to night and summer to winter, so I don't think it was the temperature.

I'm willing to bet it was something with the water chemistry.

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I'm not your neighbor, you Bakersfield trash.

I've seen cories die within 2mins of being added to a tank with water from an identical source except 7degrees colder. The original tank had water changes frequently from the same source of water but the water in that tank was heated while the other wasn't. I also add cold water to my tank and have never had any problems but considering the size of tank and water change I usually deal with the temperature doesn't drop more than 2-3degrees.

See, the thing is, we dont do huge water changes like every six months. He does a water change about every 3 weeks, cause we do have good filtration. As far as nitrAtes go, we dont have a kit to test that with, and dont yell at me for this! but we havent tested our tanks in a while because things were going so well! its just frustrating, that they just die! ]:| As for today, every one seems to be ok, we put an air line on our powerhead to get some good O2 going in the tank, and that seemed to have helped the pictus that is left! Usually with water changes, temp has never been a problem, so i am out in left field...

72 gallon bowfront:Tanganyikan Lake set up
75 gallon: A. Baenschi trio,Cyanotilapia Afra Cobwe(4), copadichromis trewavase, protomelas sp. tangerine tiger(breeding pair)

A drastic change in ph will kill. I'm not sure if it will kill instantly because I've never had a huge change in ph.

After a time the buildup of nitrates, among other things will lower the ph. The fish will gradually become used to the lower ph and will seem be fine. But a large water change will raise the ph enough to kill the fish.

In very low ph situations the bacteria in your biofilter will slow or stop the processing of ammonia. But in very low ph situations ammonia exists as ammonium.

Ammonium is not toxic so will not kill the fish. But when you do a wc that is big enough to raise the level of the ph to where ammonium turns back into ammonia the fish die.

If you do not have live plants or you do not change enough of the water, the nitrates will build up.

I do 50% or more once a week to keep nitrates low and ensure my ph stays near the ph of my tap.

Mike

Id put money on it being either temperature or ammonia disturbed from substrate.

MikeR got it right. It's why some people think water changes are bad.