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Advanced Aquarium Concepts

Before Fish Are Added

These are all articles that are most helpful before fish are added to the aquarium.

Why Quarantine Frequently Does More Harm Than Good

The stage between buying the equipment and adding fish can be very short. The first step is to get everything done discussed in the Before You Fill the Tank article. Then get everything setup and running. Make sure all pumps and filters are working. Check for leaks. Allow the heater to bring the tank up to the proper temperature. Now is the time to get the substrate and all decorations into the tank. Make sure the temperature is correct and stable. Test pH, nitrate, etc.

If the tank is small enough to require a fishless cycle this must be done before fish are added. Fishless cycling is the process of adding liquid ammonia to the aquarium daily. This provides a food source for the ammonia and nitrite consuming bacteria and allow them to develop large enough colonies to consume all waste produced by the first fish added to the tank without subjecting them to the stress of ammonia and nitrite spikes. Raising the tmperature in the tank can allow the this process to go much faster. The upper 80s is ideal. Do not forget to lower the temperature before fish are added. On the first day you need to add small amounts of ammonia at a time and test after each addition. You need to bring the concentration up to 4-6ppm. Add up the amount of ammonia it took to accomplish this. This is the amount of ammonia you need to add every day. Test the ammonia and nitrite at least once daily. You should see the ammonia start to go up and then back down. As it starts to go back down the nitrite concentration will go up and then start to go back down. Ammonia must be added to the tank every single day to keep the bacteria from dying off. Once the ammonia and nitrite both go all the way back down to 0ppm the tank is cycled. Do a large water change (at least 50%) to get the nitrate concentration back down to no more than 20ppm. You must continue to add ammonia daily until the day before fish are added. This will keep the bacteria alive and thriving, ready to handle the waste produced by the first fish that are added. This whole process can take as little as 12-15 days but is very important in smaller tanks because even a small amount of fish added to smaller tanks can cause extremely stressful and toxic, killing the fish. In larger tanks (at least 75 gallons) if very few fish are added the tank can go through a 'silent cycle'. This means that although there were not enough bacteria present to handle all of the waste produced initially, the volume of water is enough to keep the concentration of ammonia and nitrite undetectable and therefore not stress the fish. However, this does require at least a few weeks before adding the second batch of fish.

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