If you’re new to aquaponics or your setup is struggling a bit, you might be thinking of adding a swirl filter.
Unlike other aquaponics filters, a DIY aquaponic swirl filter is designed specifically for removing the solid waste from your system.
Where biofilters focus more on giving nutrient cycling bacteria a place to colonize, a swirl filter removes the other half of the fish fertilizer issue.
They can also help with water quality when a system is a little more densely stocked and prevent waste from gumming up your grow beds.
You could buy one, but like many other things when it comes to aquaponics, you can easily make your own at home.
In this article, we’ll talk all about swirl filters from what they do to how to make your own inexpensive one at home.
Removing fish waste in aquaponics without a swirl filter can become a daunting task!
Aquaponic filters do not have to be an expensive venture, a DIY swirl filter will be just as productive as a store bought filter.
A Swirl Filter Helps Remove Solid Waste
You’ve probably heard about the benefits of biofilters and how they can help turn your ammonia into useable nitrates, but swirl filters are different.
Rather than focusing on the liquid part of the waste equation, an aquaponic swirl filter uses a combination of friction and gravity to separate the heavier solids from the more convertible ammonia.
Water gets pumped into a meshed chamber, sort of like a sieve and breaks up as it tumbles around in the flow.
The lighter elements are then sucked out through the outlet valve while the solids sink to the bottom of the filter.
Unlike other aquaponic filters that cut the solids off from even entering the chamber with some sort of pad or netting, a swirl filter keeps your water cleaner with fewer filter changes needed.
With a swirl filter, the waste from your fish isn’t trapped inside the tank with them or clogging up the end of another pipe.
And as such, you’ll end up with cleaner water and much happier fish.
Swirl Filters Can Allow for High-Density Stocking
One of the great things about adding a swirl filter rather than or in conjunction with other kinds of aquaponic filters is that the aquaponic swirl filter is specifically designed to help keep less waste in your water with the fish.
Instead of dealing with murky, frothing water, and potential harm to the livestock you’re raising, their solid waste is pumped out and separated from the more easily converted parts of the fertilizer.
It’s this very trait that makes swirl filters so advantageous to high-density stocking.
When all the waste that would normally affect the health of your fish is pumped away, the only real concern with space is how much room your fish have to swim without bumping into each other.
More aggressive fish probably still shouldn’t be overstocked, especially not when small fish are mixed with large.
But calmer species like catfish do just fine rubbing shoulders together.
Overstocking aquaponics without a swirl filter will cause havoc for you when you try to remove fish waste.
Use a Swirl Filter to Keep Your Grow Beds Clean
More than the benefits for your fish, an aquaponic swirl filter will keep your grow beds looking fresher longer.
Over time, solid waste that makes it through your system will gum up your grow beds and give them a slimy, dirty look.
To make your system look better and avoid plant rotting diseases, it’s necessary to remove this film and clean your grow media.
But unlike other aquaponic filters, a swirl filter takes most if not all of that waste and traps it away from both your fish and plants.
Cleaning it out is as simple as draining the muck out of a bottom outlet.
Often a system doesn’t even need to be stopped during this process, and it can even be a useful moment for a little water change.
Though, if you don’t do as many water changes or go long periods without letting out the sludge, you may want to stop the system for at least part of that change, so you don’t let too much water out.
Swirl filters will help keep grow beds clean of fish waste before it becomes a problem, also, allows you to add more fish for aquaponics.
Make an Aquaponic DIY swirl Filter at Home Out of a 55 Gallon Drum and a Laundry Basket
Once you’ve decided to add a swirl filter to your setup, you might find yourself looking at all the different options.
Purchasing a commercial filter can set you back as much or more than a hundred bucks, but you can just as easily make your own swirl filter at home.
All you need is a large container with a lid like a 55-gallon drum, a tall, plastic laundry basket, piping, and something to cut holes with.
Take your rain barrel and cut one inlet hole about a little lower than halfway up the height of the drum.
Then cut the outlet near the top.
Cut the third outlet a couple of inches from the very bottom.
Plug the lowest hole with a nozzle so you can drain the muck off the bottom when your system is full.
The inlet hole connects to your fish tank while the higher outlet connects to your grow beds or a filter further along the chain.
Add Biofiltration for a Better System
One of the great things about aquaponic filters is that there’s no one size fits all.
You might need a biofilter.
You might need a swirl filter.
You might need both or even neither depending on how the rest of your system is set up.
But you can also always go for the melting pot approach.
Add biofiltration into your swirl filter by putting a bio media into the drum.
This can be as complicated as commercial bio media or as simple as something like finely chopped up sponges.
While this might catch some of the solid waste as it spins, the majority of the less desirable fertilizer will still sink the bottom.
Then you can reap the benefits of a biofilter and a swirl filter in the same space required for one.
Use Things from Home for an Aquaponic Cheaper DIY Swirl Filter Setup
Most people probably don’t have a spare 55-gallon rain barrel sitting in their backyard, but there certain parts of a swirl filter that can easily be made out of stuff you already have at home.
Old netting or a mesh laundry basket can serve as part of the inside.
Spare piping from other projects can make up part of the inlet and outlets.
If you choose to add bio filtration to your aquaponic swirl filter, you can use stuff you already have.
Chopped up straws, bottle caps, and cut up sponges all work well as an inexpensive, but effective bio media.
Depending on the scale of your setup, you could even experiment with alternative containers like a 5-gallon bucket, disinfected litter pails, or pretty much any container you’re likely to have to lie around the house.
But be sure to be careful of any buckets that may have contained noxious chemicals.
Even with a thorough cleaning, the leftover residue may harm your fish.
Add Multiple DIY Filters (swirl filter and biofilters) for Big Systems
If your system is a little more on the large size, you may want to consider multiple aquaponics filters.
Whether that means more than one aquaponic swirl filter or a staged type filtration system is going to depend on your time and space constraints.
If you happen to have enough room for staged filtration, then that will offer the ultimate precision between each step.
But if your space is a bit more limited, then combining the two kinds is a perfectly acceptable way to get the most out of your system.
When Aquaponics does not Need a Swirl Filter to Remove Fish Waste
In aquaponics, it can be a hassle to remove fish waste without a swirl filter, even though it is possible.
We keep talking about big, but honestly, aquaponics can be pretty small.
There are people feeding herbs and event carrots with just the water from a betta fish tank.
So while a swirl filter can help maximize the efficiency of a more extensive system, there are definitely going to be setups that just plain don’t need one.
If you have a smaller setup with plenty of good quality growing media like pea gravel or lava rock, then chances are you don’t particularly need any aquaponic filters.
However, you will need to do a water change more often. We have written a guide about how to properly execute a water change, click here.
A small mesh screen over the ports that lead to your grow bed or layered grow media system does well enough for filtration.
But always keep in mind that the less filtering you’re doing, the more you should be testing the quality of the water.
In short, an aquaponic swirl filter can add another layer of filtration to keep your setup running at peak efficiency.
Unlike other aquaponic filters, a swirl filter is more focused on removing the solid waste half of the fish fertilizer.
They allow for higher density stocking without sacrificing your water quality and keep grow beds looking clean.
You could buy one or easily make your own from less expensive items and can even work in biofiltration at the same time.
That makes this particular tool one of the most useful in your aquaponics repertoire.
Will a swirl filter help me remove fish waste? Yes, swirl filters are some of the best filters to help remove fish waste.
How much money can a DIY aquaponic swirl filter cost? The price may vary based on many different factors. You can get away with building your own swirl filter for under $50.00 USDA.