How Much Filter Floss Do I Use In My Filter?

Last Updated on February 19, 2022 by cmoarz

Using too much filter floss is a huge waste of money due to the fact you need to replace it every week or two. But using too little means it becomes ineffective and waste, and won’t do any cleaning. So how much filter floss do you use?

How much filter floss should you be using in your filter?

How much filter floss do I use? The problem with giving a static answer is it will be different for everyone based on the type of filter you have, the size of your aquarium, how many fish you have, what type of media it is, etc. I can’t give you a number on say use x amount of floss in your filter but I will try to cover some generalities that may help.

Some quick rules of thumb

Add enough floss to fill your filter so water can’t flow around it, but don’t cram it in there so it is so stuffed it hinders water flow or destroys your supply of filter floss on every change.

For a small HOB filter, that might just be a small square or 2, And for a large canister, it might be a large sheet.

Most filters will have multiple layers of mechanical filtration, such as sponge layers that trap the larger debris. In this case, you may only need to use a thin sheet to accomplish desired water clarity.

For example, in a canister filter that has a coarse sponge layer under a fine sponge layer, you could use a small thick circle of filter floss without needing to fill the entire canister up.

If the water level seems hindered and outflow is slower than usual, there’s a good chance you are using too much.

There’s no need for waste, you will still need to change the filter floss out every couple of weeks regardless of how much you use, So adding more won’t mean you can wait longer to change it. It just amounts to wasted floss and money.

Why it’s important to not overuse it

The most obvious reason not to overuse your floss is the price. While filter floss is very cheap for bulk amounts, adding too much can make it an expensive mistake. It serves no purpose as it will still need to be changed regularly unlike the rest of your filter media that holds onto your beneficial bacteria.

Too much can also mess with water flow and make the filter less effective at cleaning.

Speaking of effectiveness, If you use too much floss, Only the front portion is getting used. You may pull it out and notice the front is completely brown whereas the back has barely begun to change color. This is all wasted potential of the filter floss.

So bottom line: Use enough filter floss to fill the floss chamber in your filter, But don’t pack it down and don’t overuse it. A little goes a long way and once it’s time to replace it, toss it and add some new floss. No need to overuse floss.