if a fish dies in th tank.

Suppose if a fish dies in th tank. Do we need to change th whole water or some %
As I hve done whole tank cleaning last month only? ???

 

If a fish does in the tank I suggest doing a 25% water change even if you have just done one. At least a 25% water change needs to be done weekly as part of your maintenance schedule.
Carol

 

I think it depends on how long he was dead in your tank. If he just died over night, I don't think you have to do a big water change, if you need to do one at all.

 

Doesn't take long for a dead fish to cause an ammonia spike.
Carol

 

.... and most fish deaths are due to poor water conditions even a spike of nitrate, uneaten food... waste etc can cause some sensitive fish to die. Its a good idea to do a water change, especially when there are no physical evidence of how the fish died in the first place. A water change couldn't do any harm that's for sure!

 

We'll usually do a complete water change and clean the tank (keeping the substrata and filter sponge wet) if a fish dies as a precaution and have the tank cycled and clean for the next fish.

 

Water changes never hurt and are the first line of defense against a problem be it real or potential
Carol

 

What I've been doing (since I've lost quite a few fish at the beginning...) ....

When a fish dies, I obviously remove it, then I know I have to do a water change. Before I do so, I test the water to see how much of a change I have to do.