This filter is based on a Tetra Brilliant sponge filter replacement sponge and is designed for a vertical application in small tanks of 10 gallons or less. It has approximately the same bio-filtration capacity of a Brilliant filter but allows for a smaller footprint in the tank, thus making it more applicable for small tanks.
We start by cutting the two tubes to length. The uplift tube is inserted into the sponge as far as it will go. A small mark is put onto the tube to indicate the depth. We cut the tube about 2 inches longer than the depth of the sponge. The air tube is about 1 inch shorter than the uplift tube.
In the shop, we heat a drill bit with a torch and while hot, insert it through the uplift tube at a steep angle. The hole is just large enough to allow the air tube to be pushed through and at an angle to allow the air tube to be pushed to the bottom of the up lift tube. Do not leave the air tubing in the up lift tube for the next process.
We then take a small nail and using a pair of pliers heat the nail and push it through the uplift tube in numerous places. This allows the water to be drawn through the sponge in various locations thus making for a more effective filter.
The air tubing can now be inserted into the
up lift tube. This may be a little difficult as the nubs and burrs left from making all of
the little holes makes for some challenges. It is easy if you are patient.
When you have inserted the air tubing you can then insert the two assembled tubes into the sponge. Compete the project by using silicon sealant to "glue" the large washer onto the bottom of the sponge. You can mitigate the oxidation (rusting) of the washer by taking a little of the silicon and rubbing it all of the washer before you dab larger amounts onto the washer and glue is down. You will have to prop the filter upside down until the silicon is dry.
The next day...put the filter to work. It
does work and it works very well.