Do I Still Need To Cycle Aquarium If....

[Dmbandstef]

I use established filter media, possibly with gravel from established tank? Im a little iffy on the gravel part because there is some kind of parasite going around (head twitching, rubbing on gravel, one affected fish keeps swimming to top for air, what is wrong?)

 

[fluttermoth]

No, you don't. It's filter media that cycles, not tanks or even filters.
 
Having said that, it is possible to get some loss or die back of bacteria, especially if you'd rather not use the current gravel (it's not such an issue with sand substrates), so you should keep feeding to an absolute minimum for a few days before and after the change and make sure you test often, for ammonia and nitrite, for a few days afterwards as well.
 
You might see small spikes in ammonia or nitrite, so be prepared to do a few extra water changes while the bacteria recolonise.

(head twitching, rubbing on gravel, one affected fish keeps swimming to top for air, what is wrong?)

This is best dealt with in your other thread, so you have all the info in one place.

 

[noobgamers]

if you have used established media you should be fine but just stock in very small amounts untill you are sure shoudl be finethough if all is well then stock at normaly

 

[Rak9378]

If it were me I would be hesitant to use the filtered media if it was coming from a tank that is not 100% healthy.