1. You should take out any carbon filters in the aquarium when you are medicating your fish. The carbon in the filter will remove the medicine from the water, so it is best to remove it all together.
2. You need to have some healthy natural bacteria to process the wastes and chemicals in your aquarium. This will take around 4 weeks to grow naturally, but you can purchase products to speed up the process.
3. You should always stay up to date on the new and exciting practices for fish keeping. Subscribe to several news letters to keep up to date. If you like to read, go to your local library and get some books on fish keeping.