• DIY Sponge Filter for Shrimp Tanks

    This article should show you how to build an effective and safe sponge filter for your shrimp tank. It's relatively cheap and easy to build in approximately 20 minutes. You need these things to build the filter:
    • a sharp knife and a small scissors
    • a piece of plastic tubing, ~1cm in diameter, 15-20cm long
    • a short piece of plastic tubing, ~0,3cm in diameter, 2-3cm long
    • air tube, 2/4mm in diameter, ~23cm long
    • a fine sponge, ~5 or more centimeter in diameter, ~10cm long
    • glue
    • a L-shaped piece of tubing which fits into the long tubing (use it if you want, it's not really necessary for the filter effect)

    At first cut with the help of the knife an oval hole approximately 1.5cm below the end of the big tubing. The whole is necessary for the short piece of tubing. It should look like this when you finished cutting the hole:

    Now introduce the small piece of tubing into the air tube until it looks like this:

    Then push the bare end of air tube through the small oval hole of the big piece of plastic tubing. If you see the end of the air tube coming out, you can pull it until it fits tight (that is the reason why the air tube should be a bit longer then the plastic tubing). It should look like this in the end:

    At this moment you need the glue to fix the short piece of tubing with the air tube. Later you connect the air tube to it and it looks like this:

    Now use the scissors to cut the air tube inside of the plastic tubing until it is approximately 1-1.5cm shorter than the plastic tubing. It should look like this:

    It is necessary for the air and water flow in the plastic tubing. If it is too long, air would come out of the plastic tubing and there are less bubbles which push the water through the tubing. If the air tube is shorter than the plastic tube it works much better and looks like this:

    It would be even more effective, if you use a small air stone at end of the inner tubing. The bubbles will be finer and the whole filter will be quiter. If you want to use a 'Hamburger Matten Filter (HMF)', a flat piece of sponge (filter mat) in front of one tank side or one corner where a pump is behind it to pull water slowly through the filter mat, your are almost ready.

    You would have to cut only a small hole into the sponge to push the L-shaped end of the tubing through the mat, install it in the tank and your Hamburger Matten filter is ready.

    But such a filter is relatively big, so we use only a piece of sponge for the filtration instead of a whole mat. To optimize the water flow through the sponge, cut with the knife some holes in the lower end of the tubing.

    Now take the sponge, cut with the help of the scissors and the knife a hole in the middle of one end of the sponge and push the end of plastic tubing in it. Now your filter is ready. It should look then like this:

    To attach the filter on one tank side, use one of these small holders with a sucker for the inlet tubes of external filters.

    I use such filters for many years now in my tanks and I am satisfied with them. Of course you can buy a similar one too but it is cheaper to make them yourself and you can make them in any size and shape you want. For small tanks of less than 100litre/~26gallon such a filter is quite good for the biological filtration and absolutely safe for shrimplets.

    Keywords: DIY, filter, sponge, sponge filter, DIY sponge filter, HMF filter, Hamburger Mattenfilter