Lost 7 fish today. City water bad? :((((

[KarEn]

  I did a water change today in my tank. Got home in about 3 hours.... And almost fainted. :-(
7 fish were dead after water change.
No idea what happened.
One 8 inch pleco, two fronts and 5 julies...
Nothing was different with this water change. Kept this fish since 2001...
So sad...
Have alpha male Frontosa 9" left with three Julies, I hope they make it.
Added some salt, water conditioner. Praying....

[Darth]

did you add prime to the water? this time of year the water is treated heavily with chloromine, prime would help remove it

[KarEn]

did you add prime to the water? this time of year the water is treated heavily with chloromine, prime would help remove it

I did. In fact, I opened a new bottle of Prime yesterday, which I bought at BigAls yesterday. I added maybe 50% more of it than usual. That would not cause the issue.
Was babysitting the tank all night - alpha male frontosa and 3 Julies are ok. Front's eyes got slightly cloudy after the water change. Water's temp only changed by 1 degree after the water change. That has never been an issue before. Filters are clean, tank was clean, water chem was norm...

[fischkopp]

Sorry to hear, loosing fish this way is never fun! One possibility for what caused it might be dissolved air bubbles. These days with the water being a lot cooler it contains a lot more dissolved air, if it is being released slowly it can harm the fish severely. Did you notice a lot of air bubbles in the tank after the water change? Do you splash the water back into the tank to release most of the dissolved air?

[KarEn]

Sorry to hear, loosing fish this way is never fun! One possibility for what caused it might be dissolved air bubbles. These days with the water being a lot cooler it contains a lot more dissolved air, if it is being released slowly it can harm the fish severely. Did you notice a lot of air bubbles in the tank after the water change? Do you splash the water back into the tank to release most of the dissolved air?

I actually always connect the water hose into the Eheim filter when filling the tank. This way it cleans water as much as possible. Three were no air bubbles. I have a Hydor powerhead that's breaking the water surface as we all a very strong pump delivering a good amount of oxygen into the tank.
This is a very mature tank which I started back in 2000-2001.

Very very upsetting. I am unsure if I stock back later or give my remaining fish to a good home and be done with the hobby.

[az]

did you use water right away after mixing with prime?

[KarEn]

I emptied about 40% of the tank. Added prime. Added water. Added more prime. Always did that way.

[Stussi613]

Just wondering, are you pushing water straight from the tap directly into the filter?  If so, you're exposing the water with chloramine, designed to kill bacteria and algae, directly into your filter media and it wouldn't get treated with the prime until it comes out of the filter.  You may have actually crashed the cycle in your tank if you're doing it that way.

[Peekay]

So sorry for your losses.   

[veron]

Very sorry to here about the fish. Some how you got lucky all these years if thats how you were doing water changes.
The new water should IMO sit in a bucket/can  with PRIME over night. I always like to give some time for reactions to occure/finish. Adding water to the tank and then PRIME is not the right way. Chloramine is not easy to break down
as Chlorine. The byproduct is Ammonia. So by Priming new water in the tank you probaly released Ammonia quickly
and it killed the fish. When I make saltwater I let it sit overnight as well just to let it ''balance''
How did you balance the temp right out of the tap? did you try to adjust both warm and cold water taps?
Might have been a ph issue as well.  Sorry for this loss I know it sucks.

[lucius]

I'm still doing the bucket method with my 90 gallon.

A few days before a water change, I fill up a 30 gallon garbage can with water using a safe drinking hose (lead free) and plastic hand nozzle.  I was told that the agitation from the hand nozzle would dissipate the chlorine/chloramine quicker.  Then I add the heater to the garbage can except if it's for my goldfish tank.  I use buckets to remove and add water.  Prime gets added in the tank and not the garbage can and only once the filters are running.  On my smaller tanks, I use the Big Al's water conditioner instead.

[bergenm]

Just a suggestion, open the bottle of Prime and smell it - it should have a strong sulfur odor.

It's not unheard of for people to buy a bottle, take it home, take the Prime out, refill with water and the return it to the store for a refund.

The next person to buy the bottle loses all of their fish...

[Darth]

Just a suggestion, open the bottle of Prime and smell it - it should have a strong sulfur odor.

It's not unheard of for people to buy a bottle, take it home, take the Prime out, refill with water and the return it to the store for a refund.

The next person to buy the bottle loses all of their fish...

as metallica would say "say but true"

[Peekay]

Just a suggestion, open the bottle of Prime and smell it - it should have a strong sulfur odor.

It's not unheard of for people to buy a bottle, take it home, take the Prime out, refill with water and the return it to the store for a refund.

The next person to buy the bottle loses all of their fish...

Really?!   
I think I'll be checking the seal from now on. 

[KarEn]

Just wondering, are you pushing water straight from the tap directly into the filter?  If so, you're exposing the water with chloramine, designed to kill bacteria and algae, directly into your filter media and it wouldn't get treated with the prime until it comes out of the filter.  You may have actually crashed the cycle in your tank if you're doing it that way.

I use two ehems. 2213 and 2215.
I push water via 2213, while 2215 provides filtering and maintains bio cycle in the tank. It takes about a day or a little more for 2213 to rebuild bacteria bed.
If that was the only filter, of course I would not be doing that.

I greatly appreciate everyone's suggestions.
I will note all of the info you provided.

Happy holidays to everyone!

[76brian]

I use two ehems. 2213 and 2215.
I push water via 2213, while 2215 provides filtering and maintains bio cycle in the tank. It takes about a day or a little more for 2213 to rebuild bacteria bed.
If that was the only filter, of course I would not be doing that.

I greatly appreciate everyone's suggestions.
I will note all of the info you provided.

Happy holidays to everyone!

That's a really silly way to do your water changes IMO.

[Stussi613]

I use two ehems. 2213 and 2215.
I push water via 2213, while 2215 provides filtering and maintains bio cycle in the tank. It takes about a day or a little more for 2213 to rebuild bacteria bed.
If that was the only filter, of course I would not be doing that.

I greatly appreciate everyone's suggestions.
I will note all of the info you provided.

Happy holidays to everyone!

I've used a filter to push water out of the tank, but never to refill it.  I'd suggest not running untreated water through your filter(s), just put Prime in the tank and refill directly into the tank. If you've got a way to store and pre-prime the water then I'd say to do it, but I've done up to 50% water changes on my 135g by removing water, adding Prime and then refilling into the tank and never lost a fish...even when I was keeping discus.

[Jeff1192]

I would agree that it's probably not a great method to push the tap water through your filter. However, I also don't think there is any need to treat the water overnight in a bucket. I used to keep a 90 gallon that I did about 50% water changes on every week....so there was obviously no way to treat the water overnight. I just added it directly with a python adding Prime before and after. I did it this way for years and never had any water-change related die-off.

I would be concerned about the damage you're doing to your bio-filter at every water change. If you're only running a 2215 and a 2213 on your 125 I would think that killing off the bacteria in the 2213 would cause some problems. If I had to guess I would say that was your problem. Maybe up until now you were getting lucky?

Jeff