How To Clean Filter Socks (Save Money By Doing This)

Cleaning filter socks is not my favorite thing to do. Now that I think about it, I don’t know anyone who enjoys cleaning them.

But here’s the deal. Cleaning the filter socks in your saltwater tank doesn’t need to be a nightmare. 

With proper planning and a system in place, you can use and re-use filter socks effectively and save money while doing it.

Many hobbyists that don’t clean their filter socks just throw them away once they are dirty and replace them with new ones. Although that might be convenient and easy to do, it’s not the most affordable way. The cost of filter socks can really add up when you are changing them quite often. So to avoid spending money on new filter socks, why not clean the ones you have and reuse them. 

In this article, I will show you some great tips for cleaning your filter socks the right way.


How to clean filter socks – my favorite method


Washing machine

I know there are many different opinions on what is the best way to clean filter socks. I choose to clean mine in the washer machine. Yes, just toss them in the wash. I find this method is convenient, easy to do, and the filter socks will come out looking brand new and ready to be reused again.


First, remove the filter socks from your sump and turn them inside out. Put them in the washing machine by themselves using the hot water and delicate settings. Add 2 or 3 capfuls of bleach to the wash. Only use fragrance and dye-free bleach. No additives. Do not use any soap or detergents. At the end of the wash, you can run an extra rinse cycle to ensure the bleach has been rinsed. Hang them to dry or use a dryer on a low heat setting.


A few things to note about this method. If you have an older washing machine, you might want to run it through an empty hot water wash and rinse cycle to make sure any soap residue is removed. Not usually a concern with newer machines.

If you are choosing to dry the filter socks in the dryer, which I personally do, use a low heat setting with no fabric softeners or chemicals. Keep in mind it only takes a few minutes to dry. No need to leave them in for long. 

You may notice a small scent of bleach on the socks after cleaning. This is not a concern. 

Use the proper bleach dispenser in your washer. They usually have a specific place to add it. 

Pressure washing



Another easy method to clean filter socks is to pressure wash them. This doesn’t take long to do and within a few minutes, your socks will be clean and looking new again. If you have a pressure washer at home to clean your car or house, you can easily use it for filter socks. Make sure to turn the socks inside out first and spray away. No soap of course. Just clean high-pressure water.

Bucket method

This is probably the method that takes the most effort. Fill a bucket with fresh hot water. You can use RO water or most people just use tap water which is way easier. Then add 2 or 3 capfuls of bleach to the water, add your filter socks and let them sit for a few hours. After you remove the socks from the bucket, rinse off any remaining debris.

Then you should add the socks to a bucket of dechlorinated water. Use a product like Prime which will remove any ammonia and chlorine in your tap water. After that let them hang to dry for a few more hours and they will be ready to use. Prime is available at Marine Depot here.



As you can see, this method is a bit tedious. I recommend either using the washing machine or pressure wash methods. Try each method and see what works best for you. 

Why use filter socks?

Filter socks are used mainly in sump systems for added filtration. They filter the water that drains from the main display and traps debris and particles keeping your water clean. They are effective as a mechanical filtration source and are available in different sizes and materials. 

Types of filter socks – felt vs nylon 

Filter socks are available in either a felt or nylon mesh material. Mesh filter socks are less expensive but clog less frequently. They can either have a drawstring that can be used to tie around a drain tube or they will have a plastic ring that will fit inside a filter sock holder which sits in your sump.

The felt filter socks are a thicker material that will need to be changed more often but does a better job of filtering and polishing the water keeping it clear. They have a plastic ring around the top that fits inside a sock holder. 

Filter socks are available in different microns from 100-600. Microns are the pore size of the particular sock. A 100-micron sock will filter more than a 600 sock. The lower micron filter socks will clog faster and will need to be changed more often. Most people use a 200-micron filter sock that is either 4” or 7” in diameter which seems to be the most commonly available and affordable. 


How often should you clean filter socks?

It’s important to clean your filter socks regularly. The biggest downside of using them is how often you need to clean them. I personally remove my socks from the sump and replace them with clean ones every 3 days. Every tank will be different but after 3 days you will notice how clogged and dirty they can get.

Leaving them in the tank dirty for long periods of time is not an option. I find leaving them in for longer than 3 days will cause nitrate levels to rise and poor water quality will result. This can be very harmful to fish and other livestock in the tank. Dirty filter socks do more harm than good. I clean my filter socks on a scheduled maintenance day.

If day 3 doesn’t happen to be on that day, I make a plan to do it anyway. Yes, I might miss a day here and there but for the most part, every 3 days works for me. 

I always make sure to have a few extra filter socks on hand that are either new or cleaned ones ready to go. I simply remove the socks from the sump and replace them right away with fresh ones, then either clean the ones I just removed or place them in a bucket and wait until I have a few ready to be washed. That way I only run the washer once every 2 weeks or so. Since I use the washer to clean them, this process only takes a few minutes to complete and I always have a spare set on hand ready to be used.

Marine Depot Aquarium Supplies

Can you wash filter socks in the washer?

Yes, you sure can! This is my preferred method to clean filter socks. Just follow the steps mentioned above.

How much bleach to use for cleaning filter socks?

There is no set amount of bleach to use. I will use 2 or 3 capfuls and it works well. Some people may use a bit more or less. There is no harm in adding a bit more, just use within reason. 

How often should you change your filter socks?

As mentioned above, you should plan to clean your filter socks every 3 days. Depending on your tank, you might get away with a few extra days or even a week but I don’t recommend that. Stick to a 3-day schedule and you will get into a routine that works well for you and your tank.

How to dry your filter socks?

When it comes to drying your filter socks, you really only have 2 options. Using the dryer and hanging them out to air dry. You never want to use wet filter socks just out of the wash. Of course, using the dryer is the easiest and fastest option.

If you decide to air dry them, you can place them on a drying rack or clothesline. You can also just prop them onto a stick or pole. Let them dry outside for a few hours to ensure there is no bleach smell or chlorine left behind. Leave them to air dry even longer if you didn’t use a dechlorinator like Prime.

How to save money using filter socks

If you are one of those people that want to use filter socks but don’t want to clean them, the cost can really add up as you will be constantly buying new ones. To save a bit of cash, here are some tips.

Check out the current price of filter socks at Marine Depot here.

Buy in bulk

Usually, when you buy a large pack of filter socks you will save money versus buying them individually. You might pay $5 or more for each sock individually or buy a pack of 12 for $40. You can even buy 4 packs for around $15.

Wash and Reuse them 

As mentioned, washing and reusing your filter socks will save you the most. Filter socks can be reused many times over. No need to buy new ones all the time.

Also if you have a few extra socks, you can let the dirty ones sit for a while and wash several socks all at once. You don’t need to wash each sock right away. Run the washer once every 2 weeks instead of every 3 days. 

Manually clean vs machine cost

If you want to save a few extra bucks on power usage cost, you can choose to manually clean with the pressure washer or bucket methods and air dry the filter socks instead of running your washer and dryer every few days.

DIY filter socks

You can also choose to make your own filter socks to save money. Many people do this and really all you need is some felt material, plastic ring, and a sewing machine or sew by hand. You can even reuse the plastic ring so you only need one of them. Spending $5 or $10 on material upfront will most likely allow you to make a few filter socks that will last many weeks by reusing them over and over.

When to throw away used filter socks?

The best way to know when a filter sock is no longer effective and it’s time for a new one is when the stitching starts to let go or the material becomes thin or torn. New filter socks will be more effective than ones that have been reused many times and showing signs of wear. 


Cleaning your filter socks is something that is necessary if you plan to have them on your saltwater tank. They do a great job of filtering your water. Yes, cleaning them can be a tedious task but it doesn’t need to be. Make a plan and set a schedule for cleaning them. Have a few extras on hand so you can simply remove one and replace it right away. Just remember to change them out every few days or they can do more harm than good!