How to Clean Your Fish Tank Without Killing Your Fish

Everyone who owns fish, especially with a larger tank, experiences the “meltdown”. Despite best efforts you wake up or come home one day to find the inside of the tank covered in a greasy green film and waste clinging to everything inside. It was fine yesterday, so what happened?! Sometimes a bacteria strain can flourish in the right environment or temperature and take over the tank. Over feeding and poor care in water replenishment can upset the PH of the water. Before you go breaking out the tools, scrubbers and cleaners stop and taking the time to consider the following. The life of your little friends might depend on it.

If you have a small fish bowl, quick cleaning is simple and easy to do. Using a small net, carefully capture your fish and move them to another bowl that has never been cleaned with soap. Make sure you have room-temperature water in the bowl. There’s no harm in pouring their current tank water into the container you place them in while you quickly clean their own fishbowl. Rinse their fishbowl very well, making sure to clean the sides and get all the debris out of the gravel. Since it requires so little gravel, I often simply replace the existing gravel with new ones. If you have any “props” like signs or divers, etc clean them off as well. Do not use soap. They can be easily cleaned with hot water. Once the tank is clean, replace the gravel and props, add a dechlorinator and carefully replace your fish with the net. Discard any old water you had, don’t reuse it.

Small square aquariums should never be broken down like fishbowls. The best thing to do is clean them out once a week. You can pick up a siphon tool from your local pet store or aquarium shop that can be used to clean off the rocks and gravel as well as props in the tank. Several vacuum attachments are available to clean the inside glass of your tank as well. Once you’ve cleaned everything thoroughly inside, you’ll want to drain about 30% of the total volume of the tank. Once you’ve finished, rinse your bucket out completely and replace the water you removed with fresh clean water at room temp or as close to the temp of the tank water as possible. It’s is imperative that you do not use tap water, especially if you live in the city. Most cities treat water with chemicals, including chlorine and chloramine, which are toxic to fish. Make sure you use a dechlorinated water.

Under no circumstance should you ever clean a fish tank with a soap or any kind of cleaning solvents. Regardless of how well you rinse, there will be a residue left on the glass and contents that is also toxic to the fish. It could result in severe distress of the fish, making them agitated, lethargic, and unable to eat. It’s more likely to cause shock and death of your fish. If the waste and residue you’re trying to clean off is stubborn, and warm water isn’t working you can scrub using salt as a scouring agent. Just make sure you rinse thoroughly. It’s only recommend that you break down a small aquarium if the tank is bad. Most of the time you should be able to quickly clean it without having to empty the contents and break it down. Do not use salt to clean your tank if your fish are still in it, you could cause distress in the fish.

Breakdowns of larger aquariums, even smaller ones, isn’t really recommended because you’re taking away many beneficial bacteria in the tank that are helpful in maintaining a proper PH balance in the water. It’s best to do partial water changes once a week, as this alone will remove much of the waste products that build up as time progresses through the week and your fish poo on everything in sight.

Avoid tearing down any tank larger than 5 gallons. It’s extremely time consuming and takes a very long time for the PH of the water to return to the normal level that your fish are used to, and could cause them great stress.