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quelle filtration?


Different pumps

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as well as filter media

There are 5 main types of filter:

-1 - the box filter or angular filter : it is used less and less. The box filter is modulated by an air pump, which circulates the water through the filtering mass and at the same time ensures efficient aeration of the aquarium (rejection of bubbles on the surface). These filters are certainly very inexpensive but only the largest models could be suitable for the goldfish tank. Biological filtration is correct; on the other hand, the mechanical filtration (suction of the largest particles) is poor. Finally, they are very ugly. This filter is a good candidate for the quarantine tank (easy bacteria seeding).

-2- The compact internal filter : economical and very popular, this filter can be used in tanks up to a good hundred liters for the largest models. It is fitted with a swivel nozzle or not, with variable flow rate (it is better) or not, and now more and more often equipped with a "venturi" system to ventilate the aquarium thanks to small bubbles. Avoid "mini internal filters" for goldfish as they were designed for nano (miniature) aquariums and therefore do not have the capacity to process waste produced by axolotls. In conclusion, provided you do not choose a model that is too small, the compact internal filter is quite well suited to modest volumes (see the question of the flow a little lower).

-3- the under-gravel filter : very popular in the past, this filter is now replaced by the compact internal filter, which is more practical. This inexpensive and discreet filter is only suitable for modest volumes and requires the prior installation of perforated plastic plates placed slightly sloping under the aquarium floor (recommended gravel thickness above: 75-80mm ; gravel diameter: 3-5mm). The water is then sucked through the ground and then ejected into the tank thanks to an air column (vertical tube) generated by an air pump (aerator) and / or a water pump as appropriate. It is the gravel which in fact acts as filtering material here: particles and organic waste are attracted under the substrate (mechanical filtration) and then are degraded thanks to the action of bacteria naturally present in the soil (biological action). However, this filtration has a number of drawbacks: it must be placed first when setting up the aquarium and cannot then be removed without having to remove everything; the biological efficiency is excellent but the mechanical efficiency is poor; maintenance (suction of waste from the bottom) must be very regular, otherwise the filter risks seeing its flow rate slow down or even become clogged; finally, this filter is not well suited to the growth of plants because its action disturbs the roots and any nutritious soil is prohibited (it is always possible to have plants that do not require rooting, such as Anubia or Java fern ). Not suitable for an aquarium with axolotls.

-4- the "settling " filter is a plastic block with 2 or 3 compartments. A water pump, located in the last compartment of the filter sucks and circulates the water through the filtering mass (for example filter wadding, filter ceramics, synthetic foam cubes, etc.) to reject it purified at the surface of the tank . The biological efficiency is better than for the compact internal filter because the volume of filter material is more generous. It is an efficient, economical, easy to maintain filtration method well suited to medium volumes, the main drawback being that it is bulky and not very discreet (the heating can however be hidden there).

Another system also allows you to make your own decanter, but for this you need a piece of furniture that can be closed to put the tank or aquarium containing the pump and filter media underneath:

-5- the external filter   is an option certainly a little more expensive but devilishly effective for medium to large volumes (from a hundred liters for the most compact models). The external filter is also very versatile (the choice of filter mass is very wide: foams, ceramic noodles, activated carbon ...) The two pipes (inlet and outlet) of the filter are very easy to hide, behind plants by example. It is necessary to conceal the equipment (in the cabinet) and to ensure from time to time that the pipes are watertight. ( You will find links to buy these filters at attractive prices also at the bottom of the page )

Another important point : filtration on activated carbon is possible with axolotls but only after drug treatment. Indeed, the principle of charcoal is to absorb these molecules but the trouble is that releases them, which is why it is of no interest to have them in your filter permanently because it will be able to destroy the bacteria. , worms) you place your charcoal in the filtration and then leave it for five days, after which it releases all the products.

The pump should filter at least 3 x the aquarium liter. So for a 200 liters you will need a pump with a power of 600 Liters / Hour.

To calculate the volume (liter) of an aquarium we measure the facade x the depth and height. It will of course be a gross volume because there will be decoration, plant sand and then we do not necessarily fill up to the top.

Filter flow rate and maintenance Whatever filter is chosen, the hourly filtration flow rate must be 3 times greater than the volume of water in the aquarium. More and more filters are now equipped with a variable flow rate, which makes it possible to adapt the flow rate to your needs. When the flow decreases markedly, the foams or other filter media are then rinsed, but never with tap water because the foam contains essential purifying bacteria which are very sensitive to chlorine. If the aquarium filter is equipped with only one foam (compact internal filter), care should be taken before changing the foam (usually after a few months) to avoid sacrificing the entire bacterial colony all at once: either by rinsing twice. We will only change half at a time and the second half two weeks later. The old block will thus have the time necessary to colonize the new one and enough bacteria will be preserved! Important: the aquarium filter must run 24 hours a day, 7 days a week. After a 3 hour shutdown, the colony is largely considered dead because, no longer being stirred and oxygenated, the bacteria die. It can be useful to have battery-powered bubblers available in the event of a power failure or to operate the pump in a bucket, the important thing being that there is always a stirring carried out in the filter media allowing the life of bacteria in also bringing oxygen.

Efficient biological filtration: The more the filtering mass contained in the aquarium filter (for example block of blue foam, lava, ceramic noodles, pozzolana, etc.) has a large filtration surface, the more effective the biological filtration. This pleads in favor of a filter of suitable size for the axolotl tank because they are big "polluters". Here is an ideal and inexpensive bacteria fixative. We buy these bags in garden centers and DIY stores.

If your filtration system has just broken down, all is not lost: put the filter media (foams, ceramic noodles, etc. in a bucket with the "juice contained in the pump and aerate using a bubbler until replacement If there is a power cut, the same operation with a battery-powered bubbler as for a move elsewhere.

The pozzolana is used to make pretty alleys. These are crushed volcanic rocks. Around € 6 for a 15 / 20kg bag. Remember to rinse it well then place some in tights (more practical for cleaning) and add them to the filter media of your pump. Its capacity to fix bacteria is superior to those of ceramic noodles (but not for the same price) for tanks accommodating fish you can place it under your substrate  

It is a fully biological filtration. The impurities are stopped by the foam, they fall at the foot of the foam and are sucked up during daily cleaning. The foam is never or very   very little rinsed. About once a year. The foam surface to be used is to be calculated according to the liter and the volume of the pump. The slower the filtration, the more efficient it will be. There are very few elements that make up the filtration. A basic submersible pump of 2 to 3x the volume of the tank and a block of foam (medium blue foam or similar at least 3cm thick ). Depending on the surface of the foam, it is placed in a corner or across the width of the aquarium. Considering my litrage I had to place it on the width. It's not pretty at first but over time the foam becomes more discreet . For the minimum size of the foam surface we take 3X the volume of the pump, in my case 700x3 = 2100cm2 BUT we are looking to have a ratio lower than 10 imperatively , the lower it will be, the slower the filtration will be and therefore effective since bacteria have more time to do their job. A ratio of 0 corresponds to a zero filtration rate. The calculation of the ratio is to be done like this. V being the filtration speed (flow per square cm of foam) V = (liter X pump flow) / (6 X foam surface) = For example my Aqua: V = (260 X 700) / (6 X 2100) = 14.44 ... 14.44 ... being above 10 I have to enlarge the foam surface. After various conversations with myself I opted for V = (260 x 700) / (6 x 4500) = 6.74 ... So I need 4500cm2 foam. Being limited to 50 in height I must take 90 in length to obtain 4500cm2 Hence the position on the width of the aquarium. It was a usual break-in. A beautiful brown mass settles in the filtration part, it must not be removed. The pump is itself almost never rinsed, when the flow drops at worst every 6 to 8 months lol and again. In fact I think it's the exact middle ground between classic filtration and low tech. Since we let the filtration live by just cleaning the tank.

In addition to this, you will need to know more about it.

Article by Bou Roggero-Claudon

Elements of filtration:

In addition to this, you will need to know more about it.

Mousses - wadding (perlon) - ceramic noodles

Wadding (perlon)

Fine filtration of small particles

Foams, medium grain filtration

Ceramic noodles, excellent support for bacteria

Click on the images to be directed to a merchant site

1000L / hour

1400L / hour

2000L / hour

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