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How to Perform Your Weekly Water Change

If you’re new to aquariums, you may be unfamiliar with how to perform water changes. You know, however, that it is essential to do water changes on a regular basis to maintain your aquarium(s). The simplest way to perform this task is to use something called a siphon, in addition to a bucket designated only for aquarium use. It is important to only use buckets that are free of soap residue or that haven’t been used for household cleaning. Failure to do so can contaminate your aquarium and may even result in fish dying.  If you so choose, you can invest in a Python siphon, which eliminates the bucket entirely. A Python will hook up to the nearest sink and it comes in a few different lengths. It uses the water pressure coming out of your faucet to drain your aquarium water directly into the sink. Every week, you want to take out anywhere from 25-50% of your aquarium water. This will reduce nitrates and remove detritus build up and keep your fish happy and healthy.

Python No Spill Clean and Fill

Ways to Start a Siphon

There are a few different ways you can start a siphon. First and foremost, it’s important to have your bucket for collecting water lower than the aquarium. A siphon will rely heavily on gravity to function. This is not an issue, however, with the Python as the water coming out of the sink will work to pull dirty water out of the aquarium. But for all other siphons, you will want the water to flow up and out and then below the aquarium water level. Some siphons on the market will feature either a squeeze bulb or a valve that makes starting it easier.

You can also buy a squeeze bulb and attach to the end of your siphon. Then starting it is only a matter of giving the bulb a few squeezes. For siphons with the valve, you have to move it up and down rapidly a few times to get water flowing. For more stubborn situations, or for a very basic siphon, you have a few other options.

First, if your aquarium is big enough, you can submerge the entire siphon into the aquarium. You want to sink it in the water until all the air bubbles come out. Then you cap off one end and move it out of the aquarium into the bucket before uncapping. The water should begin flowing immediately. Another way you can start a gravel vac siphon is to submerge the wide end of the tube. Once all the bubbles are gone, cap off or pinch off the end of the tube going into the bucket. Lift the gravel vac into the air in a cupping motion. Then release or unpinch the tube until the wide end is half-way emptied of water. Cap or pinch the opposite end. Then submerge the gravel vac end of the tube, making sure all bubbles are evacuated. Then uncap or unpinch the end going into the bucket. The siphon should start immediately.

One can also suck on one end of the siphon to get it started faster, but this isn’t advised as it exposes you to various germs and bacteria in the tank.

How to use the ""gravel vac""

When siphoning an aquarium, you want to move the wide end of the hose, or the gravel vac portion, around the substrate. You should see detritus and fish waste being removed as you go along. You want to be careful not to suck up any small fish or the substrate itself. If your aquarium has sand, you may want to gently stir the substrate before placing the gravel vac just above it. This will avoid pulling out loads of sand into the bucket. You can also pinch the tubing to prevent finer gravel being sucked up, or to move the siphon from spot to spot to maximize the amount of detritus vs. water you remove. You will stop once you’ve reached roughly 25% of your aquarium’s volume removed and then you can dispose of the water and begin filling.

How to Fill your Aquarium

Whenever you are filling an aquarium with water, you want to be sure that the water you’re using is the appropriate temperature as well as treated to remove chlorine and chloramines. Josh’s Frogs Tap Water Conditioner does a good job of treating water. If you are filing with a Python, you should add the dechlorinator directly to the tank as soon as the water starts coming out of the hose. Be careful to check temps as you fill; if you add water that is too cold or too hot, you can shock your fish and possibly kill them. Making sure the water is no more than 5 degrees off (cooler or hotter) will keep your fish safe.


Once your tank is filled, you have completed your weekly water change. If done properly, it only takes at most a half an hour of your time. This should be repeated every week to keep the nitrates low and the tank in balance. Check out our blog here for more information about why water changes are important.

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