Should You Clean The Gravel Every Water Change?

There are varying opinions online on whether or not you should clean your aquarium gravel every time you change your aquarium water.

Some hobbyists think you will remove too much of the beneficial bacteria in your gravel, but if you remove too much beneficial bacteria with a quick vacuum then your aquarium probably isn’t going to make it anyways.

You should clean your gravel with a gravel vacuum every time you do a water change to remove detritus, fish food, poop, etc. Just don’t completely remove the gravel to clean it. A quick gravel vacuum will work just fine.

Bare with us and we will explain in more detail…

How Often Should I Clean Aquarium Gravel?

The key to knowing how often to clean your gravel is to know how often to change your aquarium water.

To figure this out you need to test, test, test!

You should have an API water test kit for your aquarium.

Test your water every week and when the nitrates reach 30-40ppm you need to change your water which is when you would clean your gravel with a vacuum.

How To Properly Clean Your Aquarium Gravel

Make sure to turn off all of your electrical equipment and unplug it for the risk of electrical shock.

You should drain some of the water from your tank with your gravel vacuum or water changer to make it easier to get to the gravel with your gravel vacuum.

You will need enough five-gallon buckets to hold the water you are sucking out of your aquarium.

Another reason to turn the equipment off is that the water level will be too low for the heater which could kick the thermostat on to heat up thin air.

Also if the filter is above the water level, it will be sucking in the air instead of water.

You should also scrape the insides of your aquarium so the gunk falls down onto the gravel or into the water you will be sucking out of the aquarium.

You can follow the instructions for a python-type water changer that uses a faucet for suction or to simply run water back into the tank.

Some vacuums come with an air sac to get the suction going but with the most common ones, you simply submerge the vacuum under the water and tip it up, then back down to start the suction.

Why You Need To Clean Your Gravel With A Vacuum

When you vacuum you remove a lot of fish food and poop, and dead plant parts.

You actually remove tiny pieces of these though that you wouldn’t notice.

If you left all of this waste in your aquarium, you would have poor water quality because this stuff decomposes and leaves ammonia in the water.

This ammonia can harm your fish and is the reason you cycled your tank in the first place. If you keep this waste cleaned up regularly, your nitrites and nitrates won’t rise as fast

A problem with gravel is that there is space in between the pebbles which can hide this waste and develop anaerobic bacteria that consume sulfur and then release hydrogen sulfide into the water if they are cleaned later.

You will know if this happens by the smell of rotting eggs which will signal you to remove the fish while cleaning the gravel and changing the water.

Will Cleaning The Gravel Too Much Remove The Beneficial Bacteria?

When you vacuum you do not pick up enough of the beneficial bacteria to do any harm.

Most of your good bacteria live in your filter which is specially designed to host beneficial bacteria.

If you remove too many beneficial bacteria from your substrate and your water quality crashes then you didn’t have enough beneficial bacteria in your aquarium in the first place.

You can also use products like betta beads, bio balls, rocks, socks, etc. For beneficial bacteria.


I hope we have shown that you should clean your gravel every water change and why.

Some people prefer to vacuum their gravel every other water change instead-but if you do it every time, there will be less waste to vacuum up each time.

Happy Fishkeeping!

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top