Let fresh water sit out overnight to dechlorinate, or treat the fresh water with a dechlorination product. Wash your hands and make sure you’ve washed away all residue of soap, lotions, and other potential contaminants. Dry your hands with a clean paper towel. Disconnect any electrical appliances near the fish tank to prevent any risk of accidental electrocution. Wait to reconnect those appliances until you’ve finished changing the water and checked that everything is dry. For an otherwise healthy tank, you can aim to replace about 30% of the water. In a 10 gallon (37. 9 L) tank, that means replacing 3 gallons (11. 4 L) of water. You don’t necessarily need to remove the fish for a partial water change. Just be careful as you put your hands in the tank so you don’t startle the fish. Scrape off any algae that’s grown on the walls of the tank. You can buy a specialized tool for scraping algae, or simply use an old credit card. Use a siphon tube to drain out 30% of the old water into a bucket or nearby sink. When you’ve removed enough of the old water, slowly pour in the fresh, dechlorinated water.
Uneaten food is a large contributor to ammonia levels. Fish waste can also cause spikes in ammonia as it decomposes. Dead plant matter or dead fish left in your tank will release large concentrations of ammonia. Try cleaning out the filter in your tank, as this could reintroduce built-up organic matter back into the water. Don’t replace the filter pads, though, as you may upset the bacterial balance in the water.
Make sure your fish is still getting enough food. Talk to a veterinarian or fish expert on how much food your fish needs to stay healthy. Be aware that changing your fish’s feeding habits won’t reduce ammonia levels that are already high; it will, however, prevent future spikes in ammonia levels once the water has been changed.
Some people introduce bacteria by putting one or two inexpensive fish in the tank so that the fish’s waste can bring in bacteria. If going this route, you may use a goldfish for a cold water tank, barbs for a warm tank, or damselfish for a saltwater tank. You can also add healthy bacteria by introducing a handful of gravel from an older fish tank to your new fish tank’s bottom.
Adding chemical pH adjusters (from your local pet store) is probably the easiest way to lower the pH of your tank. Lowering the pH won’t remove the ammonia, but it can render it less dangerous if you need to buy some time before you can change the water. One easy way to maintain lower pH levels is to make sure you use actual gravel for the substrate (bottom) of your fish tank. Using crushed coral or coral sand releases calcium in the water that can cause spikes in pH. [5] X Research source
Aeration won’t do much in a large pond, but it might help manage ammonia levels in your fish tank. You can buy an aeration pump at most pet stores or online. Make sure you leave your tank uncovered if you normally have a lid on. As the ammonia gas diffuses, it will need to be able to travel outside of the tank.
Neutralizing drops do not actually remove ammonia from the water. Instead, the drops will neutralize the toxic effects of ammonia, rendering it harmless in the water. You’ll still need biological filtration (from bacteria) to break down ammonia into nitrite and nitrate.
Use the ammonia testing kit you would use for the fish tank on your tap water. If the ammonia levels are high in your tap water, talk to a representative from your municipal water district.
Any decomposing organic matter, including aquatic plants and microorganisms, can cause a spike in ammonia levels as protein breaks down. Uneaten food can also cause spikes in ammonia levels as it breaks down in the water. [9] X Research source Scoop out any matter that shouldn’t be in the tank promptly. Make sure you maintain your tank’s regular schedule for changing or partially changing the water.
You can manage fish waste by scooping out solids whenever you see them and changing or partially changing your tank’s water on a regular basis.
As a general rule, if your tank is established (meaning it’s been inhabited and has active bacterial colonies), you should not be able to detect any ammonia with a standard kit. If these tests indicate a measurable level of ammonia and you know there is already a healthy bacterial colony and a lack of organic matter, it’s most likely a problem with your filter.
The pH of a body of water affects how much ammonia is ionized versus how much remains un-ionized. You’ll still need to treat the water beyond adjusting the pH, as acidifying the water will not actually break down the ammonia that’s already present.
Ammonia levels reach their peak approximately 90 minutes after your fish have been fed. Testing the water shortly after your fish have eaten (and are producing waste) can give you an inaccurately-high reading of ammonia levels.
