Is It Safe To Reuse This Filter Immediately?

[fishnovice]

Just found my lovely young marbled con dead. She was OK last time I checked yesterday and body shows no sign of injury or disease. She was in a tank on her own for 3 weeks cos she was being bullied. Is it safe to use the filter from dead con's tank for fry tank? If not how should I treat/disinfect filter before reusing it? Need it for fry tank.

Funny thing is, this is the 2nd unexpected fish death in 24hrs -the other was a danio in a 2nd tank which started swimming funny with bent tail immediately after 50% water change and died later that night. Other surviving danio and jewel in 2nd tank are unaffected so far. Both tanks were in the same room but danio has never been in contact with dead cichlid. Did big water changes on both tanks at the same time. Could it be the water?

 

[aly_starh]

If you are positive that there was no disease that killed the fish, then the filter is fine if you want to use it again. It will most likely be cycled enough for use with fry.
But if there was a disease, thats a whole different thing, you will have to clean and dis-infect the tank and also kill the bacteria in the water with regular chlorinated tap water.

EDIT: what are your water statistics currently, the dead fish lying in the tank may have caused a slight spike in Ammonia.

 

[OldMan47]

It is entirely possible that it is the water you used for the water change. The town where my local fish club is located does occasional "break point chlorination" which means the chlorine is a very high concentration. Anything much less than a double dose of dechlorinator while they are doing that means dead fish are soon to follow.