Orangehead tapajos dying after water change

[cpm6t]

My tapajos die after I do a water change.
So far I've bought 10 tapajos and 6 of them have died on 4 occasions. Each time the death was the following morning after the water change day. When I get up one or two is dead. There are other fish in the tank (such as small peacock bass, teters etc none of them died).
I do about 50% water change at a time. Empty half of the tank, put the water directly in to the tank from garden hose while adding anti chlorine. I add the specified dosage, if not little bit more.
What is going on here? Appreciate your help.

 

[UnstoppableJayD]

water from the house is not the same temp?

 

[cpm6t]

No they are at the same temperature. About 75F I would say. How come only Tapajos are dying after the water change? The small peacock bass would be sensitive at that size I would say. I have never lost any other fish after a water change, ever. :-(

I was planning on having a separate tank for Eartheaters only. With this happening, I'm not so sure any more.

 

[Mr.dempsey]

Check your tap water I lost a whole tank of mbuna once do to my tap water getting increased ammonia levels.

 

[petspoiler]

^Agreed. You need test results from your water to help figure out what's going on. That is a starting point. without that it's only guessing.
Your tap water parameters could be varying from time to time, so test everything- ph, ammonia, nitrites, nitrates. Repeat tests before doing water changes.
Chlorine vs chloramines is an issue for which water conditioner you need. and the level of concentration determines dosage. Your water treatment facility should be able to tell you that info.

Sometimes tap water comes out over-saturated with oxygen & I've read that can kill fish (never experienced it myself).
If that is happening you have to let water settle a few hours (?) in large safe container before adding to tank.

I have done every percentage of Lg water changes with earth eaters and never had a negative result, always positive.
My geos are f1 redhead/orangeheads & wild caught heckelii (threadfin acaras) take it fine, very happy afterwards. even though my ph is about 7.8 & the wilds likely came from lower ph, no problem.
ph shock can kill fish so compare your dirty tank water to incoming tap levels.

 

[duanes]

Is the garden hose fairly new? plastic?
Some of the new garden hoses contain a chemical to keep them subtle, and that sometimes leaches out. Geos are sometimes a bit more sensitive than others.

 

[IRONWOOD]

that sux

 

[cpm6t]

I don't have the facility to test the tap water for chlorine. My water supplying authority is not helpful that way either. I have tested tap water before for nitrates, it came out zero. Ph is around 7.0. But I know it is water now since the last tapajo in that tank was almost dead, I pulled him out, put him in a water bucket with water from my pond with two air stones and he is doing much better now.
My guess is that it has to do with the chlorine content of the tap water (probably has large variations) and I guess I'll have to age it in a separate tank before water changes here after. Oh man, I wish I could save the other 3 that died today morning.

 

[Catfishracer]

How often do you do the water changes? Any shells or driftwood as decor?

I'm suspecting a PH swing. If you tested your tank water right before water change, and also tested the new water before putting it in, I bet you would see the issue.

I never recommend pH up or down additive or anything like that.

Simply doing smaller water changes more frequently.

Sent from my SM-N900V using MonsterAquariaNetwork App

 

[neutrino]

I don't have the facility to test the tap water for chlorine. My water supplying authority is not helpful that way either. I have tested tap water before for nitrates, it came out zero. Ph is around 7.0. But I know it is water now since the last tapajo in that tank was almost dead, I pulled him out, put him in a water bucket with water from my pond with two air stones and he is doing much better now.
My guess is that it has to do with the chlorine content of the tap water (probably has large variations) and I guess I'll have to age it in a separate tank before water changes here after. Oh man, I wish I could save the other 3 that died today morning.

Are you using a water conditioner? Might seem like a stupid question, but chlorine should not be a factor if you're using something like Prime or Stress Coat properly and sufficiently.