I was kicking around ways to substitute improved filter media into my Fluval Spec V and found some people in forums suggesting common materials to substitute. Among them were nylon pot scrubbers, scotch-brite pads (dollar store scrubbie pads), filter wool, polyester fill (polyfill – found at craft or fabric stores for pillow batting). That got me to thinking and I checked out what was available at the dollar store.
I found a great little combination scrubber and sponge in the cleaning section.
It has a flat pot scrubber on one side, similar to a scotch-brite pad. The other side is a fine sponge. I bought the package of two for about $1.16 USD.
How to Use in a Fluval Spec Aquarium
The length of the sponge fits perfectly inside the filter section of the Fluval Spec Aquarium; I just needed to trim the width down to about 2-1/2″ (64 mm). A set of kitchen shears made quick work getting it down to size.
I was a little leary about this cheap sponge having some chemicals in/on it, so I rinsed heavily in tap water, then I let it soak for an hour in dechlorinated tap water in a small tupperware container.
After it was thorougally rinsed and cleaned, I wedged the sponge/scrubber above the Fluval filter and below the removal handle. It just barely fit below the handle. I considered cutting the plastic handle off but it’s actually nice having that to remove the filter media. I mounted the sponge with the scrubber side up. It is more coarse and will catch the big stuff first, leaving the finer sponge second. This add-on filter media works well at the top since you can remove it and clean it separately without disturbing the main components of the Fluval filter.
How well does the scrubber/sponge combo work?
I like how it has performed in my little nano aquarium. The stock filter material in the Fluval Spec is allright, but the sponge filter that serves as mechanical filtration is a bit coarse and the large holes allow too much detritus through the tank. That is where this added sponge filter on top helps a bunch. I cut it so that it fits very tight and not much water bypasses around it. The water flowing first through the coarse pot scrubbing section and then through the finer sponge really knocks down the particles floating around the tank.
I think the price is very good. Each sponge will cost about $0.50 each and I anticipate they will last a few months. They will essentially be throw-away media that will protect the Fluval filter sponge and hopefully keep it cleaner. As part of my weekly maintenance, I will just squeeze out this sponge on top to get the big stuff out.
The only odd part of this configuration is that water can bypass the top scrubber section when it enters striaght through the return slots. I don’t think it’s a big deal. With the way it fits so well in the filter section, all the water has to pass through some part of this sponge and it does a great job of clarifying the water.
The filtration components for this Spec V are really coming together. I am currently running: DIY dollar store scrubber/sponge, stock Fluval sponge filter, Fluval Biomax (in the upper section of sponge filter), and Seachem Purigen 100ml Bag (in lower section of sponge filter). Deciding to not use the stock activated carbon bag and instead use the purigen helped make the water clearer, but I think this little sponge filter has helped just as much.
A Word of Warning for DIY Filter Materials:
One thing to consider when sourcing filter materials that are not specifically made for aquariums: You are taking a bit of a risk that the sponge, pot scrubber, poly-fill, or other material you are using may have chemicals that are not friendly to aquariums. I took the risk and it worked out fine. All my fish and shrimp are perfectly healty. Do as I did and make sure and rinse anyting out througally. Avoid cleaning products that say “antibacterial” as they surely have chemicals that are bad for your tank inhabitants. Once you find a source for material that is proven clean and healthy, don’t change! Keep using the same product and be on the lookout for changes in packaging that may indicate a change in the product.
There are some good, and safe, filter materials available online.
Update: Aquarium Specific Products are Better:
Since I wrote this article, I have discovered a few aquarium specific products that are available that not only outperform the pot scrubber filter I wrote about here, but they are actually cheaper too!
I have a full writeup here. They are a two stage system with the first being a Bonded Blue & White Poly Filter Floss Pad and the second a 100 Micron Polishing Filter Pad. Not only is this system much more effective than my homemade solution here, it is actually cheaper (if you replace it regularly) – a pair of each cut to size for a Spec aquarium cost about $0.38 USD each.
Homemade solutions still may make sense for those who don’t have access to specialized bulk aquarium filter media like these.