How to Get Rid of Detritus Worms in Your Aquarium

First off, it’s important to remember that you likely won’t be able to get rid of every single detritus worm in your substrate. 

In fact, a small detritus worm population living in your aquarium is a good thing. Most aquariums have at least some of these little critters living in the gravel/soil, and no one even notices them. 

They eat poop and uneaten fish food, helping to break these wastes down.

You just don’t want a huge population living in your tank.

They’re unsightly and kinda gross. And if the population grows too large, they can even deplete the oxygen in the water.

Luckily, keeping detritus worm populations in check is quite simple.

Detritus worm overpopulation is caused by one or both of two things: 

  • Poor substrate cleaning practices 
  • Overfeeding

Gravel Vacuuming

Gravel vacuuming aquarium

In order to get rid of the detritus worms that you currently have, do twice weekly water changes on your tank including thorough gravel vacuuming. 

The suction from the gravel vacuum will pull the worms out so you can dispose of them. 

I know it can seem daunting to clean your substrate, especially if you have something other than regular gravel or have plants. But, don’t worry, it’s actually pretty easy.

You don’t have to dig very deep into the substrate in order to suck the worms out. So, you don’t have to disturb the entire substrate bed to get the worms out. 

Here are some tips for cleaning different kinds of substrates:

  • Gravel – this is the easiest kind of substrate to clean. Just dig the gravel vac all the way to the bottom of the tank again and again in all the open areas. Push the vacuum lightly into the top inch or so in planted areas. 
  • Sand – the trick to vacuuming sand is having a long lift tube on the gravel vacuum and slowing down the flow of water by kinking the drain hose. This helps stop sand from escaping through the vacuum but will still pull out worms and fish waste out. 
  • Soil – because soil substrates are so light and easy to disturb, it’s really important to slow the water down. This means having to work more slowly, but you should be able to pull a lot of the worms. 

Once you have reduced the worm population, you can switch to weekly water changes. Just be sure to continue vacuuming the substrate to keep the worm numbers low. 

Stop Overfeeding

Detritus worms can’t become overpopulated without a substantial food source. 

A giant population boom means that too much food is going uneaten and collecting in the substrate. 

detritus worms in substrate

Overfeeding is one of the leading causes of problems among fishkeepers. Fish like to eat and we like to feed them.

And fish will continue to beg for food even if they’ve had more than enough to eat. They always act like they’re starving, prompting us to give them way more food than they need. 

But don’t believe their lies! 

Only feed your fish what they can eat within about a minute or two. 

Watch them eat to make sure that all the food gets eaten up. Don’t just dump food in and walk away. 

Remove uneaten food promptly. You don’t have to track down every stray flake, just do your best to keep things to a minimum.

You can also add invertebrates like shrimp or snails to clean up food scraps. 


Detritus worms are just a part of life when you have an aquarium. 

But, if they become overpopulated, they can be gross and unsightly. 

Luckily, it’s really easy to get rid of the overpopulation and keep it gone. And it’s stuff you need to be doing anyway, so no big deal. 

I hope you find this article helpful. 

I wish you and your fish the very best.

Katherine Morgan
Katherine Morgan

Hey, there! I'm Katherine from Northwest Florida. An aquarium specialist, I've kept tanks for over two decades, enjoy experimenting with low-tech planted setups and an avid South American cichlid enthusiast.


  1. Thank you for your very helpful article I’ve just read …after a year of everything going wrong from dead fish.snail extream invasion equipment breaking down .had a beautiful peaceful tank a few fish and a pleco. I introduced live plants and its been down hill since then . Now these worms ..hope this works . I know understand its me overfeeding them I love watching them co.ming up and circling around . Any way rant over .. massive thank you Annie

  2. Hi!
    Can a tank become infested with detritus worms from a sand addtion?
    My wife and I have a single Tiger Oscar, currently 10+ inches in length and won’t be 12 months old until June. I moved him from a 55-gallon tank a few months ago without observing any transferrence of detritus worms from the 55-gallon tank. Yesterday, I found several floating around after I had releveled the sand bottom because Oscar tends to like to “fight” his reflection and moves the sand around. Anyway, we’ve been very, very diligent in only feeding Oscar until he stops eating. The usual ‘sign’ is that he takes a whatever we offer but swims away rather than remaining in the area that we always feed from. He gets fed twice a day and only what he will consume. I even remove the pieces that hit the bottom of the tank rather than leaving them. The only additions to the tank was a bag of sand about 2 weeks ago. I rinsed and rinsed and rinsed it until it was almost clear water after working the sand in it. It never dawned on me to disinfect the stuff. So, back to the question: Can adding sand introduce those damned worms? I really don’t want to fight this battle again, especially in a 125-gallon tank. Thank you for your response.

    • Hi David, my first question is: was it bagged sand from the store? If so, I think it would be impossible for the worms to live in the dry bagged sand

      However, tiny baby detritus worms can ride into the tank in a few drops of water. Also, they don’t only eat uneaten food. Detritus worms would happily eat all the fish poop produced by an oscar

      Definitely, keep up the good work on preventing uneaten food in the tank. The Oscar could also be cut back to one feeding per day, or lessen how much he gets each feeding. This cuts down waste. Make sure to vacuum out solid wastes so the worms don’t have it to feed on. But remember, detritus worms aren’t harmful and these happen to everyone at some point, so don’t be too hard on yourself.

Leave a Reply

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

This site uses Akismet to reduce spam. Learn how your comment data is processed.