Cheap Homemade Aquarium Filter





Introduction: Cheap Homemade Aquarium Filter

Aquarium filters are expensive, especially the replacement filters. Using things I had laying around the house, I made some of my own for under $.25.

Step 1: Commercial Filters

Commercial filters are expensive (unless they came with your tank at a garage sale, like mine).

Step 2: A Filter's a Filter...

I realized how simplistic those commercial replacement filters are, and found a substitute: air filters.

Now, these commercial filters come with carbon or other media as a chemical filter, so I just bought my own.

Step 3: Create a Pocket...

Create a pocket for the chemical media. I simply hot-glued the edges.
Be sure to squish the glue between the filter parts.

Step 4: Fill With Chemical Filter Media

Now, prior to just making my own filters, I did use commercial filter replacements without the plastic frame that comes molded to them (I don't know why there was no plastic frame; I got them free). However, those puffed up with use.

I recommend putting a staple in the center of your new filter to keep it from puffing up like that.

Add chemical filter media.

Step 5: There You Have 'er.

Insert filter.

This has been my first instructable. Give me criticism.




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    Like the idea. How's about cheesecloth that's used in making cheese and straining fine liquids from foods. It can be bought at any grocery store for about a dollar and is safer. It can be cut to size and fitted in the plastic brackets. I plan on using it for our tank. Will let you know how it works.

    2 replies

    good idea,did it work?

    I had to replace my waterbed mattress. Being it was waveless . The fiber fill in it will be enough to keep me in 12" x 12" filters for my near 600 gallon Koi pond. Tho it does clog up in 2 weeks and not something you'd want to even try to rinse out. Thank goodness I have a boat load.

    Good idea and good follow up from everyone. ty

    When I used the frame + bag cartridges I always put the bag in a jar of hot water and shook it until it was clean, that kept it from getting flattened and worn out by other means of washing it. You can use bleach if you like them white. One box of cartridges lasted me several years. Now I just get a sponge and cut it to fit the filter. Rinse it under the tap when it gets full and never worry about it again.

    Oh. You can also pull the pads and the plastic brackets out and run them in your dishwasher's rinse cycle on hot. The jets will flush all the yucky stuff out.
    Have fun.

    The staple is not going to cause any problems at all, I have been using staples to secure plants to driftwood for several years and have had no ill effects, it takes a lot non-collated iron to be piosonous, but anyway great idea and a good instructable

    3 replies

    The part I would worry about is the vent material. Some contain fiberglass and other not-so-good things for your fish. More importantly, a lot of the vent filters today are anti-bacterial and you want bacteria in your filter medium, that's why you rinse it out in aquarium water, so you don't destroy the bacteria.

    I like your instructable a lot, but I think it might be safer if polyester batting were used instead.

    What about a couple of coffee filters?

    if anyone is worried about the staple i think a dab of hot glue on the center would also keep it from puffing up.

    Why don't you use the big rolls of un-cut filter pads? They cost about $8 for a 12x8" sheet.

    I have been using the same filter pads in my tank for about 3 years now, all I do is pull out the pads, hit them with hot water in my sink, and stick them back in, never had an issue with pH jumping around, or high level so of nitrates/nitrites, though aquarium salt might have had something to do with that lol

    Great idea! I'm tired of buying filters. I've been prolonging the life of store bought filters (ie Whisper Bio-Bags) by dumping out the old charcoal, removing the filter from the plastic frame and rinsing the filter under the faucet while gently scrubbing with an old toothbrush. I would then replace the filter and add fresh charcoal (purchased from pet store). Much cheaper than using a new Bio-Bag each time. Your tip will save me even more cash by making the filters from scratch. The info about charcoal being useless is also good to know. I always thought that the charcoal played a big part in the filtration process.

    3 replies

    for future reference,
    i wouldn't clean the actual filter body, as that will have beneficial bacteria on it, acting as a biological filter, keeping ammonia and nitrite levels down.

    Good economizing! But in the future, refrain from using tap water if you are unsure of its hypochlorite (chlorine, bleach) levels. The chlorine removes the beneficial bacteria from your filter material. One option is to reserve a small amount of the aquarium water in a container and rinse, or slosh, your filter in the container. Not as thorough of a job, but the benifit to the water, and your fish, is worth it.
    Made a diy wet-dry.

    well, a good aquarium setup should have at least 2 small filters if your aquarium is around 10-20 gallons. alternate replacing each cartridge every few weeks and the beneficial bacteria will remain. larger aquariums usually already have filters that have 2 filter ports but smaller filters usually dont due to there bulky nature

    Dont forget that you can re-activate carbon by baking it

    2 replies

    This is a myth, it has to be heated to over 400degree to work.

    my oven goes to like 850... what are you trying to say?