Shrimp friendly and safe - the sponge filter

Here there is no motor and no deadly filter wheel - the sponge filter for the aquarium is classically operated by an air pump. The principle behind this is that the air introduced at the bottom of the filter tube rises in bubbles through the riser tube, taking the surrounding water with it due to the inertia of the mass. Thus, not only the air fed in at the bottom escapes the air lifter's outlet, but also a larger or smaller amount of water - depending on the strength of the air pump selected. The water is pushed upwards by the air bubbles, which creates a negative pressure in the pipe, and water from the aquarium is sucked into the pipe through the filter sponge. For this purpose, the tube, which is in the sponge cartridge, is provided with holes.

The fine filter sponge contains masses of bacteria that remove pollutants from the water flowing through it - just like in any other aquarium filter. Here, protein is metabolized to ammonium, ammonium to nitrite and nitrite finally to nitrate. The water flows slowly enough in the fine pores to give the bacteria time to do their work. What then remains is the comparatively harmless nitrate, which can be removed from the water by changing the water or by the activity of the aquarium plants.

Even with a sponge filter, the aquarium water should be circulated about 1.5 to 2 times per hour. The best way to gauge the amount of water that the sponge filter is turning over is to use a liter measure to catch the amount of water that will flow through in 30 seconds (this is best done with a stopwatch or the timer function on your cell phone). Then simply read the scale, multiply the result by 120, and you have your water flow rate per hour. If the measuring cup is not enough, use a larger measuring cup or measure an appropriately shorter period of time and adjust the number you multiply by - for example, for 10 seconds the number would be 360, for 20 seconds 180.

Besides being absolutely safe even for the smallest fry and tiniest baby shr imp, the sponge filter has another great advantage, which is especially beneficial to oxygen-loving shrimp from stream biotopes such as the bee shrimp, tiger shrimp or even taiwan shrimp, pintos and so on: the drive principle enriches the water with a large amount of oxygen. Here you do not need a separate air pump even at night to compensate for any lack of oxygen.

In addition to the filter sponge and the air lifter made of tubes with a device to which the air hose is attached, you also need here an air hose of 4/6 mm diameter in the appropriate length (which is already included in the scope of delivery for some models, please refer to the respective description in the online store) and of course an air pump available separately from us in the store. When setting up, make sure that the air pump is not lower than the aquarium, so that no water can get through the air hose into the air pump. If it is not possible for you to place the air pump for the air lifting filter higher than the aquarium, you can also install a valve as a backflow protection in the hose section, which prevents exactly that.

In terms of maintenance, the sponge filter is as uncomplicated as can be. If you notice that significantly less water is getting through, pull off the sponge, wash it thoroughly under running water or in a bucket of aquarium water, and put it back on. Of course, when setting up the air pump, you should also make sure that the air hose is not kinked. Especially at the edge of the aquarium, this can sometimes happen. You can remedy the risk of kinking with an appropriate hose guide or a piece of thin filter sponge that you attach as a cushion.

Due to the air pump and the bursting of the air bubbles, a sponge filter may not be the best choice for an aquarium in a very quiet environment such as a bedroom, but in breeding tanks, in the aquarium basement or in environments that have a certain level of background noise anyway, it is certainly the first choice for a shrimp aquarium.