Question About Filters

[Hollyweb]

With the recent problems I've been having in both my 3 gallon and 20 gallon tanks due to ammonia and nitrate levels, it was recommended to use some of the filter media from my 20 gallon tank to help establish my 3 gallon betta tank. The problem is my tap water has been coming out with an ammonia level of about 0.25-0.50ppm and that's tested both with water conditioner and without water conditioner.
 
The filters I use are the disposable kind that go with the tank kits I got. One is a Top Fin and the other is an Aqueon. I see a lot of topics where people have asked about what kind of filters to use, however my question would I be able to take out the disposable filter (which just contains carbon) and add my own filter media?
 
I'm not really sure what to do or where to start with something like that so any advice or links to other topics would be much appreciated.
 
Thanks!

 

[msebar]

If both tanks are having problems the filter medium for the 20 gallon tank will not help the 3 gallon tank. You need to establish a good bacteria bed before putting any fish in the tanks. I would try to do something to fix your tap water to remove any ammonia from it. A good water filter should do the job. Check with your local hardware store. In the mean time find some good water and do a 30% water change every day until your levels drop.