why when doing a 50% water change did my fish die?

Question

I did a 50% water change this morning and as soon as I finished my Fish died. I had put 'Tap Safe' in the water and left it overnight to settle.

Answer 1

I routinely do weekly 50% water changes on all of my freshwater tanks with zero issues. Just ensure that the water parameters of the new water (pH, GH, KH, & temperature, etc) are pretty much identical to the tank water. (if one or more of these parameters is significantly different, it can stress a fish to death). If you do a 50% water change after having not done any water changes in months, that can stress your fish to death as well.

Use a quality dechlorinator (one that removes chlorine and chloramines). I'm not sure what 'Tap Safe' is (I use Seachem's Prime), but if your water conditioner only removes chlorine and your tap water has chloramines, your fish will die.

20-33% water changes are usually sufficient, and if you are a beginner and have a light bio-load (lightly stocked tank), then a 50% water change isn't typically required.

Answer 2

Was the new water the same temp as the old water? temp spikes will kill fish also you may try a little less on the water change say maybe do a 25% instead of a 50% oh and maybe you could get a really good filter system it will help with the water change or may lengthen the time in between water changes.
Any sudden change in a fishes habitat can become fatal to them if it's drastic enough hope this helps

Answer 3

You should never do a 50% water change the most you should do is a 1/3 of the tank water change because you take away alot of the nutrients of the water that is already in there. Your fish also might juist be sick. Fish die easily I have had my goldfish since June. How do you take your water out? I use a syphon. Maybe what your taking the water out with is dangerous to the fish try using a special product ment to take water out of a fish tank.

Answer 4

i honestly not sure how great the chemical water treatment works. One of my fish died after a 10% change..

With a pretty big water change 50%, you need to let the water sit for 2 days. That seems to work for me.. I don't even bother with chemicals anymore. That's long enough for the water temp to rise to room temp and for the chlorine to evaporate.

Answer 5

You might fill tap supply water that was Chlorinated. It is dengerous for fish. you must keep the water exposing sunligt for at least 5 hour before filling into tank.