The arrangement of the bottom filters for the aquarium is somewhat different from the conventional cleaners. To filter in such a device, gravel is used, which is poured onto a special grate slightly elevated above the bottom of the aquarium.
Water passing through the soil layer leaves there all the contaminants that are subsequently destroyed by various microorganisms living in the aquarium. However, such filters are very quickly contaminated, they have to be washed with a special siphon.
But the biggest problem is a constant stream of water that passes through the ground. This is unusual for natural reservoirs. For some underwater plants, it is necessary that their roots are washed with ordinary water without excess oxygen. Otherwise, such plants form huge roots, and the leaves grow small and few.
Bottom filter with own hands
If you decide to use a bottom filter for an aquarium, then try making it yourself. To produce a simple aquarium bottom filter, a glass jar with a capacity of 0.5-1 liters is required. Close the jar with an ordinary lid and make two holes in it: for the tube and for water from the aquarium. Another cover is required for the bulkhead, and a filter material is placed between the covers.
Another version of the simplest bottom filter for the aquarium, which you can do yourself. For the body will need a clay bowl, which is laid filter material, and on top of the linings set to a normal funnel. For filtration, medium-grained quartz sand and nylon threads are taken. Aerator, as an additional device, you can buy in the store.
Bottom filters appeared in the middle of the last century and are now obsolete. However, some aquarists, especially beginners, prefer to use bottom filters. If you regularly clean the gravel and partially replace the water in the aquarium, they will economically and effectively improve the conditions of your fish.