Vacuuming the substrate in the aquarium is one of the elements of constant care for the hygiene of our tank. There are many myths related to this activity on the web, incl. does it kill the good nitrifying bacteria deposited on the bottom?

What is vacuuming (desludging) an aquarium?

Vacuuming the substrate is one of the basic hygienic activities in an aquarium. It consists in removing as much dirt and sediment from its bottom as possible. We use a desilter for this. It is a stiff tube with an extension and usually a strainer. On the other hand, it is connected to a longer, flexible hose. Some are battery operated, others connect to the sink, others operate on the principle of differential pressure and manual pump. Thanks to this, you do not have to suck water with your own mouth to start its flow. Comfortable and hygienic.

After starting the device, vacuuming the aquarium is a fairly simple process. If the ground is too deep (a few centimeters), simply collecting dirt from the ground may not be enough. How to remove deposits from deeper layers? We hammer the pipe extension into the ground and wait a few seconds for sand / gravel / stones to be pulled into the pipe extension. The heavier elements (pebbles) will fall or be stopped by the strainer, and the detritus will be removed with the water into the bucket. This operation is performed on the entire substrate. Most often, such desilter cleaners have transparent pipes, thanks to which it is very clear how contaminants are removed from the tank.

What is the desludging of the substrate?

First of all, it removes small particles from the ground – fish droppings, dead plant material or excess food. Otherwise, the remaining debris will begin to decompose, spoiling the water quality and releasing toxic ammonia.

However, if we move the substrate too much without changing the appropriate amount of water, we may inadvertently release nitrogen and phosphate compounds from the bottom sediments. This can disturb the balance in the aquarium and result in an algae bloom. To prevent this, you need to change a little more water than usual when doing general cleaning in the aquarium. You can also clean the bottom regularly in batches. When planning more solid “rummaging” in the bottom, it is worth cleaning or replacing the mechanical media in the filter a week or two in advance, slightly rinsing the biological deposits (in water poured from the aquarium) or not touching them at all. This will ensure a constant, large amount of beneficial bacteria and, at the same time, almost maximum filter performance.

Can good nitrifying bacteria be removed by vacuuming?

Desilting the substrate as part of regular aquarium maintenance will not significantly reduce the number of bacterial colonies. We suck small particles from the bottom, but not microscopic. Yes, the substrate is a great habitat for beneficial bacteria, but they live in the crevices of pebbles. By desludging the bottom, we remove only a small percentage of them. However, if the filter in your aquarium is too small, the main biological medium is the soil. In such a case, thorough cleaning of the bottom can easily disturb the biological balance.

Filters in well-kept aquariums should be equipped with biological filter media. This will ensure a constant supply of beneficial bacteria, independent of the substrate. The biologically active media include highly porous materials: ceramics, crushed lava or synthetic bio-spheres. On the other hand, sponges, cotton wool and nonwovens are used primarily for the mechanical purification of water. They trap pollutant particles but are a poor reservoir of biology.

How often should I vacuum the tank?

It is best to vacuum the aquarium regularly once every 1-2 weeks. Remember to remove any removable ornaments before desludging. You will be surprised how much waste settles under these beautiful castles or stones. Vacuuming the bottom combined with regular water changes will significantly improve the balance in the aquarium. With the removed water, you can successfully water the plants at home. It is rich in minerals, nitrogen compounds and phosphates.