3 dead zebra danio after cleaning tank

Jan 11, 2003
666
0
0
35
New Jersey, USA
#1
I cleaned out my tank and after I did a water changed I noticed that 3 of my zebra danios were acting strange, They were at the top of the tank breathing hard and then started swimming like if they had seziers. And then eventually they just died. THose are the only 3 that died. I have other zebra danios and cory and they are prefectly fine. I also noticed that I am guessing it was the cories that had fry because they are very tiny and seem to "suck" onto the glass/plants. The fry look perfectly fine. I am thinking if it was the water, it would affect the fry even more than grown fish. SO what could have happened for that to happen to them?
 

Jan 11, 2003
666
0
0
35
New Jersey, USA
#2
some things that i know could have been the cause is a change in temperature from the new water but the new water was the same temp. also the water was treated before i poured it in. other than that I am at a lose as to what caused it
 

Grymatta

Large Fish
May 16, 2005
439
0
0
#3
How much water did you replace? 20%? 50%? what did you use to treat the water?

The container you used to hold the treated water...could it have become contaiminated somehow?
 

Jul 19, 2007
819
0
0
clemson,sc
#5
a number of things could of caused their deaths...stess is one..how old are they...do you have plants in your tank...could be metal poisoning from tap..esp in such a large amount being dumped into the tank, did you clean out the filter?
 

Jan 11, 2003
666
0
0
35
New Jersey, USA
#6
i did not touch the filter. i was waiting for about 4 days so that i do not distrub everything. i only have plastic plants inside. i am not sure about their age but some of the ones that died i got 2 weeks ago and some where 1 week old.

lets say it was metal posioning, how come it did not affect all the fish?
 

blue_ram

Large Fish
Jun 21, 2008
516
0
0
Florida
#7
You should never put tap water directly into the tank, treat it and let it stand for a day or so before you put it in the tank. Chlorine and chloramines will kill fish and you have no guarantee that tap water will instantly be made safe as it enters the tank.
 

joy613

Medium Fish
Mar 2, 2008
99
0
0
#8
By chance did you check the water from your tap? Sometimes city water has ammonia in it.
I use a python to change my water, I put the water conditioner in the tank then slowly run water from the tap into the tank.
Another thing is bacteria from your hot water tank.
 

noob23

Large Fish
Dec 17, 2007
268
0
0
SoCal
#9
I just don't think you used enough conditioner. I use a python too, i had the same problem because i didn't use enough conditioner. When you change that much water with a python, and you have un-treated water entering your tank, make sure you use a pretty decent amount of conditioner.
 

Lakea

Large Fish
Oct 14, 2006
317
0
0
Texas
#10
My cousin lost a lot of platy and guppies one time, she had like 10 in the tank, changed the water, and then they had the same symptoms, only three survived. She had used some kind of cheap conditioner that was onsale at petco, that was the only thing I could thing of.

Condition your water, some conditioners take a bit of time, so put your water in a bucket or something add some conditioner and let it sit for a minute or so before you had it to the tank. Also make sure the temperature is the same, maybe it was shock from a big change in temp. And I don't know how you add water, but if you just add it into the tank with a hose or something you need to use enough conditioner to treat the whole tank and not just the amount you are putting in.
 

Jan 11, 2003
666
0
0
35
New Jersey, USA
#11
thanks for all the suggestion everyone.

I have checked my tap water for ammonia and even nirite and they were both at zero.

I know it was not bacteria from my hot water tank because since it is summer, my aquarium stays at around 78-80F and I checked my tap, leaving it running for about 2 mins, just cold water, and I got that same reading.

When I added the conditioner I just put it in one spot. Maybe I should added slowly, make sure it is enough for 10g even though I did not change that much, and have it fall into the aquarium by dropping it into the stream of the python.
 

Jul 20, 2010
3
0
0
#12
Water Changes

I changed about 50% of the water. I have a python system so I first make sure the water from the tap is the same temperature. I used the Tetra Aquasafe to treat the water
50% Yikes! I know people have different opinions about changing water, but if your nitrates are low, don't touch it. The biggest thing I have found is just don't over feed fish. I have done 2 10% water changes in my tank in the past 2 months, and I actually think that is a bit much because the water conditions are perfectly fine. I have very little to no evaporation because of my Plexiglas lid and I have a few plants in my tank.

It was probably your water change that killed your fish because a 50% water change, you basically just completely changed HALF of their life and atmosphere. Imagine someone changing 50% of anything in your house, you would flip.