Fish tank setup and cycling

How to choose

1. 01Verify stand weight capacityWater weighs about 8.3 pounds per gallon, and a set-up tank with glass, substrate and rock comes to roughly 10 pounds per gallon or more, so a 20-gallon tank can top 200 pounds. Use a level stand built for that weight.
2. 02Rinse gravel, sand and decor thoroughly in plain waterRemoving fine dust before filling prevents cloudy water and protects the filter. Planted aquarium soils are the exception; follow the bag's directions and don't rinse them.
3. 03Treat tap water with a dechlorinator before adding it to the tankDechlorinators neutralize chlorine and chloramine, which would otherwise kill beneficial bacteria and damage fish gills.
4. 04Add pure ammonia to about 2 ppm to start a fishless cycleBeneficial bacteria need a steady ammonia source to grow. Bottled ammonium chloride is easiest to dose accurately; fish food also works but is harder to measure and messier.
5. 05Wait until 2 ppm of ammonia drops to 0 ammonia and 0 nitrite within 24 hours before stockingThis shows the bacteria colony is big enough to handle waste from the fish you add.

Common mistakes

• Adding fish immediately to a newly filled tank, which causes fatal new-tank syndrome from ammonia and nitrite poison spikes.
• Replacing or washing filter cartridges with chlorinated tap water, which destroys established beneficial nitrifying bacteria colonies.
• Placing an aquarium near direct sunlight or drafty doors, leading to runaway algae blooms and dangerous temperature fluctuations.
• Using non-level or weak household furniture as a stand, resulting in structural silicone failure and tank leaks over time.
• Leaving ammonia-removing media (zeolite or ammonia pads) in the filter during a fishless cycle, which soaks up the ammonia the bacteria need.