A fountain clogs typically due to excessive debris getting caught in the fountain's pump. Debris such as leaves, plant and animal matter, and algae will clog a pump if the debris is not removed from the water. Pond owners may prevent this clogging to their waterfalls and fountains by using a pond filter system that strains debris. A simple pond skimmer can be made easily for a small pond. A skimmer is a box or container that protects the fountain pump behind mesh which catches any material before it reaches the pump.
Turn the fountain pump off and remove it from the pond water. Take off and throw away any sponge filter in the front of the pump intake. Then clean the algae off the outside of the pump as it may be making the clogging worse.
KineticFountains.com suggests soaking the pond pump in white vinegar and water to remove debris, and then to remove the pump cover and clean out the inside of the pump. This will clear out any debris that has accumulated.
Find a plastic container to use as a small pond skimmer, such as a small plastic storage bin. A large plastic food container should suffice if the pond is very small.
Cut a water intake hole into the front of the plastic storage container, and another in the lid, towards to back of the container, for the fountain's outtake to fit.
Reassemble the pump if it was taken apart to clean, and insert it into the back half of the container, away from the intake hole. Push the outflow hose, which leads to the fountain, through the hole in the lid.
Line the front half of the container with pond filter mesh or sponge pot scrubbers. These will catch any material, such as algae or leaves, that would clog the fountain's pump, so make sure that no water can get to the pump without going through the filter mesh.
Submerse the filter into the pond water using a weight to keep it down if necessary. Keep it in a location where it can be easily found again for cleaning.
Clean the homemade small-pond skimmer at least once a week or more if the water flow to the fountain seems obstructed. Turn off the pump and remove the container, then take the mesh out and rinse out the grime, debris and algae.
Use a strainer, such as a small pasta colander, to hold the filter mesh from step 6. Instead of lining the plastic container with the mesh, fill up the strainer with mesh, then insert the strainer into the container at the intake hole. Cleaning will be easier--just remove the colander and rinse the mesh inside. Do not use soap or any cleaning agent to clean the mesh if fish live in the pond. Skim the pond with a pool net to remove large leaves and floating bugs before they have a chance to get stuck in the skimmer.