- Reaction score
- 5 to 10 years
I did this last night. I set up a 10 gallon using a filter and filter media from my established 29 gallon and let it run overnight. It has been going for about 20 hours. I have read today that using old media only works if I put fish in RIGHT AWAY. So...does that mean I messed up and the old filter media is useless now???