The color designations dark brown, terracotta, white and black certainly speak for themselves and require no further explanation. The situation is already different with the special colors, so here is a brief overview.

With these special colors, the pattern results randomly and is almost impossible to plan. At the beginning of the use of a new clay ball, the pattern is usually coarser, while it becomes finer and finer as the process progresses. The goods are delivered according to stock on hand, a selection according to sample is not possible for logistical reasons.






That depends of course on the container size – ok, you would have thought so, too… 🙂

So, first of all – our FERMENDO is really high in dosage compared to many other water plant care systems available on the market. Right from the start we didn’t think it made sense to pack and sell an unnecessary amount of water. The high dosage reduces packaging and weight and thus also shipping costs. Last but not least, parcel carriers and, of course, customers are happy about less weight during transport…

Now to the question, how much do I order for my needs?

Our FERMENDO BASIS-booster is dosed with 10 ml per 100 litres of aquarium water, or 1 ml per 10 litres.
One 1 L-bottle is sufficient for 10,000 L aquarium water. 
If, for example, you have a 100 L tank and fertilise after a weekly partial water change of approx. 30% according to instructions, you can manage 100 weeks with your 1,000 ml bottle. That would be almost 2 years… Ok, no problem, the fertilizer will last for a long time. In this case, however, it would perhaps make more sense to order a smaller bottle, e.g. 500 ml (with the 100 L-bowl, therefore about 50 weeks, i.e. just under a year).

This calculation then also relativizes the price, of which one or the other will think first, oh, but that is much more expensive than the products of the competitors… :-).

The FERMENDO DAY is again more highly dosed: 1 ml per 100 litres of AQ water.
DAY is designed as a daily care. So you could add approx. 1 ml DAY daily to your 100 L-bowl and get by with a 500 ml-bottle for about 500 days…

Our floating breeding box is primarily used for the rearing of juveniles. It can of course also be used for individual fish, shrimp or crabs e.g. for targeted short-term medical treatment with subsequent fresh water supply.

The rearing of juveniles and, in particular, L-catfish requires a relatively large amount of high-quality feed. If the young fish swim freely in the tank with the parents, they often do not get enough food and the breeding success falls only moderately. In order to get as many fishes as possible, it is useful to feed them in a smaller container. A simple breeding box without active filtering, e.g. a guppy rearing box, pollutes very quickly, the feeds decays and molds. The water quality deteriorates quickly for the sensitive young fish. In this case, a relatively high maintenance effort is necessary.

Remedy is an active filtering in the breeding box. The water in the box is replaced 20-30 times an hour completely, Mulm and feed residues migrate to the filter mat and are biodegraded there as well as in other mat filters. Thus a fairly large quantity of juveniles can be fed ad libitum in a small space. For example, in our large rearing box, we usually feed up to 100 ancistren up to a size of 2-2.5 cm.

EHK Aufzuchtkasten Wasserfluss

The separate air line can be used not only for particularly delicate species, which provides additional fresh air to the water in the box interior and local water movement. For this purpose, either a second diaphragm pump is necessary, or the use of a T-piece in the existing air supply line.

A further advantage of our swimming rearing box is that it floats with a sinking water level at a water change of the parent tank. In contrast to a box attached to an aquarium wall, ours does not fall dry, assuming a normal partial water change of about 30%. Essentially for the well-being of the young fish is also the possibility to be able to hide. Our breeding boxes permit a certain payload in form of small caves, tubes, bark hiding places or clay leaves.

The main advantages of our breeding box:

  • floats in the aquarium and requires no hanging or fixation
  • with a few movements it is easily and completely disassembled for optimal cleaning
  • has its own filter system and a separate air supply
  • its buoyancy also allows additional weight such as ceramic caves or hiding places
  • no blocking of gauze interfaces
  • filter changes can be done when the breeding box is in operation, without the fish must be taken out

Data Free floating breeding box small:

Content: ca. 2,4 l
Outer dimension: ca. 23,5 x 13,5 x 12 cm (LxBxH)
Usable area: ca. 11 x 11 cm
possible additional load: ca. 200 g

Data Free floating breeding box big:

Content: ca. 5,6 l
Outer dimension: ca. 30,5 x 17 x 15,5 cm (LxBxH)
Usable area: ca. 19 x 15 cm
possible additional load: ca. 400 g

Valid for both models:
For operation, a commercially available air / diaphragm pump is sufficient. If both connections are to be used, a pump with 2 connections is needed or – with only one connection available – a distributor piece (T-piece).

Air pipe ∅ 5 mm (connection via standard 4/6 mm air tube)
fully assembled, incl. exchangeable filter mat (total 3 filter mats)

We manufacture all our clay products exclusively itself in carefully crafted. We use ceramic-lined stoneware composition, which is fired at about 1050-1100 °C. This gives the ceramic a dense surface. It can thus be no foreign substances store (as drugs after treatment of fish), and from the clay no ingredients can be dissolved cause they are tied. With us you are guaranteed to find no imported pottery.

We place special emphasis on the clean processing of the cavity edges to prevent injuries of the fish by our caves.

Because we have no machine-made mass-products, and the clay batches varies so that the greenware does not shrink equal during pre-drying, there may be slight deviations from the specified dimensions.

If you are looking for a clay article which we do not have in our program, please contact us. The preparation of individual caves at affordable prices is part of our daily business. The delivery time would be in this case, depending on the size of the piece, within 2-3 weeks, with very large, thick pieces possibly even longer.

Here are some basic informations about aquarium plants care in relative brevity. Who likes it more fully, please follow the links below.

Why add important nutrients?

Basically, our central European waters differ significantly most of the ones in which most aquatic plants used as aquarium plants are native. The composition is i.d.R. so that not all important trace elements are present in the required quantities, so it is relatively quickly without the supply of essential elements to an insufficient supply.

Poor plant growth goes hand in hand here often with excessive growth of algae. This is because algae as “low” water plants survive on less trace elements as “higher” water plants and so with trace element deficiency have a competitive advantage over the actual vegetation.

Here helps only consistent weekly partial water changes and targeted supply with iron and trace elements.

The “normal” planted community tank, however, is mostly in sufficient quantity, if not supplied even abound with nitrogen and phosphate.
The main source of this is the fish feed, which is at least partially supplied via the detour of the animal to water plants. These elements are therefore in water plant care products for aquarium usually not necessary (except plants are heavily dominated, fish aquariums poor). However, the other necessary trace elements are very often lack Substances which should be supplied in addition in order to achieve a stable, strong plant growth and to obtain (for detailed information see here).
Good water plant cares for community tanks such as the Fermendo system are therefore free of nitrogen and phosphorus.

Attend on?

  • The nitrate levels should between management measures (water bills) falling continuously.
  • The phosphate levels should also between the nursing measures (water bills) falling continuously.
  • Decreasing values of nitrate and nitrogen indicate that the nutrients supplied are consumed by aquatic plants.
  • The iron value should not fall below 0.1 mg / l fall (before the water change) ideally, slightly higher rates after dosage are not detrimental to the system.

Why should we add supplements?

How differs the aquarium water from natural water bodies?

What is the nutritional needs of aquatic plants and what is the correct dosage?

Despite the fundamental insights in plant nutrition and plant physiology, we are in the hunting and the problem that we can not predict the actual need for trace elements of an aquarium. There are several reasons:

1. Still largely missing knowledge of the specific requirement of individual water plants </ strong>
There are few published data on crop volumes and fertilizer needs of individual water plant species (Kasselmann 1999). This is probably mainly because the research of plant nutrition is concentrated on major crops.

2. Complex interactions of various aquatic plants in the aquarium
However, much more important are the interactions of a mixed culture of aquatic plants (and microbes and animals) in the aquarium itself. It is then that complex systems with nutrients to (and light) competing species. The topped up to “macronutrients” such as nitrogen and phosphate on the fish food, the lighting, the carbon dioxide supply and water quality of the water change play a role and are not precisely predictable.

3. Water tests
nother important point is the availability of sufficient quality water testing. Except for test kits for iron and copper, and the macronutrients nitrate and phosphate hardly aquaristischer manufacturer has more kits in its program. In this respect, the aquarium if it is not to other products such as the highly recommended tests of Macherey-Nagel GmbH & amp. Co. KG in Düren recourse, “usual” in the available in the pet trade tests and be watchful eye instructed.

Therefore, in principle, all dosing information to consider (any manufacturer) as a guideline. To illustrate this point, one of the test for the aquarium Fermendo fertilizer is briefly described below:

description of the test tank for Fermendo fertilizer:
Volume 1,600 l gross real about 1,400 l.
Lighting 2 x 250 W HQI, lighting time 12 hours a day, plus some strong lateral sunlight.
Type: rainbow fish, sucking loaches, some armored catfish, Otocinclus 85, some Hara hara. Overall rather low stocking.
Strong planting dominant Vallisneria gigantea, Vallisneria spiralis, Crinum thaianum and Hygrophila polysperma, additionally about 3/4 of the soil with Cryptocoryne x willisii, Cryptocoryne becketii, Cryptocoryne planted wendtii (different versions), Cryptocoryne parva, various Echinodorus, Anubias and Microsorium (on Root).

Moderate supply of carbon dioxide (about 60 bubbles / minute, thus avoiding biogenic decalcification V. A. by Vallisnerien), introduced over a 30 cm long flippers.
Water values: GH 17, KH 9 (somewhat variable), pH 8.5, nitrate fluctuates on average between 25 and 40 mg / l, tendency between water changes sinking, phosphate 0.1 to 0.25 mg / l wavering.
Weekly water change about 25% of output water 50 mg / l nitrate and more than 2 mg / l phosphate.
This aquarium has been fertilized by the beginning of the test phase with a pure iron fertilizer and held the ferrous value from about 0.1 mg / l. After the beginning of fertilization with iron Fermendo the figures have been daily measured, thereby estimating the growth benefits of aquatic plants and adjusted the dosage accordingly.

In the given circumstances, the fertilization was continuously raised to 5 times the amount of the average recommended dose of Fermendo in daily dosing to a stable iron level of 0.1 – to provide 0.25 mg / l permanently between water changes. The nitrate and phosphate levels fall between the water changes, indicating a total of consuming nutrient conditions. The growth performance of aquatic plants is more difficult to assess (measure), roughly the growth performance increased by about 30% since the beginning of fertilization. Symptoms of deficiency to the aquatic plants are not available.

Overall, one can obtain also available in pet shops water test interpretations and assessments of nutrient requirements of an aquarium, despite all the limitations of the measurement results:

1. The nitrate levels should between management measures (water bills) falling continuously.

2. The phosphate levels should also between the nursing measures (water changes) decline steadily.
Both (decreasing) values indicate that the aquarium is located in a total nutrient-sapping state, that that adequate nutrients are consumed by the activity of the water plant and the biogeochemical cycles in simple terms as a largely closed and are working perfectly to evaluate.

3. The iron value should not fall below 0.1 mg / l (in each case before the water change) ideally, slightly higher rates after fertilization are not detrimental to the system.
Interestingly, playing under such conditions also still “fairly high” values for nitrate (in the test pool of 25-40 mg / l) no role in relation to the growth of algae, this basin is largely free of algae (of course, who grew up eating fish to be considered). The high amount of light with some direct lateral incidence of sunlight is unable to cause visible algae growth.


Kasselmann, C. (1999): Aquarienpflanzen. – 2. edition Stuttgart (Ulmer)

The aquarium habitat differs in two points very clearly from natural waters:

1.    Water volume
The available water volume is based still considerably lower than in natural waters on the amount of manicured organisms (microbes, plants, animals). Each of these organisms takes substances from the water and are on the other hand again materials to the water. Also the added fish feed and its compounds are considered. This is very easily unequal distributions in the distribution of nutrients to be trace elements that plants need especially decrease most rapidly, and to increase especially the values for nitrate and phosphate.
A constant supply of trace elements for aquatic plants then no longer guaranteed.

2.    Water exchange
The second important difference is that the water continuously in natural water exchange. This of course is not “fresh” water within the meaning of tap water, but even back to biologically “processed” and “purified” water. Importantly, two factors are: 1. The removal of excess nutrient salts and 2. the continuous replenishment of the necessary trace elements. Both are given in principle in natural waters intact, this shall apply both to rivers as well as lakes (the latter in conjunction with the volume of water).

Ultimately, the continuity of the nutrients and trace elements is the most important, to be observed for the aquarists point so that fluctuations in the supply of water plants do not occur, or to move within narrow limits. The ideal aquarium would therefore be a flow tank with a continuous water exchange and in addition a continuous supply of all necessary trace elements by means of metering pumps.

This sophisticated technology is known in the reef aquarium with highly consumptive of trace elements coral dominated aquariums for quite some time and is more and more on the care and propagation demanding coral species, especially by hard corals.
In freshwater aquariums, the situation is basically similar, but take water plants slight variations in the continuous supply of nutrients less evil than hard coral species in seawater. Nevertheless, the general rule is the more often an exchange of water and more continuously, the supply of trace elements, the more secure the success in the culture and care of aquatic plants.

Our central European water differs in its composition often significantly from tropical waters. However, it should be noted that there is not the central European water, but depending on the region partly significant differences in the hardness and composition exist. Some generalizations can be stated, however, that Central European waters have an increased amount of calcium and magnesium, potassium often, however, is present only in small amounts. Of the plant trace elements are unneeded very often in water or only in trace amounts, which are quickly consumed the Aquarium of the aquatic plants.

For this reason, in planted tanks need to make an additional supply of trace elements needed to achieve a strong, healthy plant growth while preventing unwanted emergence of algae.

The run-in phase of an aquarium
After setting up an aquarium, it is found in most cases that initially aquatic plants grow very vigorously and make a vital impression. Depending on the device (for example, with additional ground), sand used and the output water, this phase can no feeding quite up to 4 months, sometimes longer be. Regular weekly water changes may extend this phase.
Later it will be noted, however, that first very demanding plants like Haarnixe (Cabomba caroliniana) or the Small Ambulie (Limnophila sessiliflora) do not grow as well and make an ailing impression. By then, the time is reached, where the water changes and the fish feed is no longer any trace elements needed by the plants are supplied to the aquarium in sufficient quantity.

Add nutrients on algae problems?
If one does not begin at this time with an additional adding of nutrients to the aquarium, the emergence of algae, especially beard, brush and thread algae is preprogrammed downright. This ‘lower’ plants are namely in contrast to the ‘higher’ water plants able to manage with less trace elements and then use holes made in the nutrient supply to permanently establish itself in the aquarium. (more…)

The following formula can be easily calculated:

L x T x H x 1,5

L = tank length
T = tank depth
H = desired level ground
1,5 = Factor Material Density natural sand

tank length = 60 cm
tank depth = 40 cm
desired level ground = 4 cm

60 cm x 40 cm x 4 cm x 1,5 = 14,4 kg

You will need ca. 14,4 kg.

Thus, you could order the following package units:
1 x 10 kg + 1 x 5 kg

Or you can simply use our sand quantity calculator.

No, aquarium sand from Granoflour® in our experience can be used safely even with armored catfish. If you are still unsure and would rather form an opinion about our sand, just ask us for a free trial!

Granoflour® natural sand can be used in the shrimp aquarium without hesitation.

Yes, that is completely without any problems. There is no influence.

No, the Granoflour® sand is water-neutral. It does not affect the water equivalents, neither the hardness nor the pH.

No, at least not to an extent that this could affect invertebrates. In small amounts is essential for this copper, but it is precisely the amount that makes something toxic or not. Here is a more detailed explanation:

The University of Cologne as used for over 30 years brass in their test facilities and therefore has excellent experience with this material-related. There are under freshwater conditions no kind of corrosion, thus no major types of “solubility”. Brass is an alloy of copper and zinc, thus comparable with bronze, the well known, consists of copper and tin. Of course we can not exclude the possibility that solve individual metal ions from alloys, but if there is no greater corrosion, it can be considered as absolutely marginal the amount, if any. Furthermore, these sintered bronze diffuser is also for some years used by someone who also produced Immersion rearing boxes, principally L-numbers. Even with these – mostly operated even under low pH – pool there was never evidence that would point to a stronger solution of metal ions </ p>.

So the answer is clearly “no”. We are sure that there is no interaction here, otherwise we would not offer as responsibly-conscious biologists something for the aquarium.

Incidentally include both tin and copper and zinc to the necessary trace elements, not only for plants. Many of these trace elements are at the same time toxic, depending on the concentration (Paracelsus). And the discussion fertilizer – shrimp, to name just one example, provided that one would flip an entire bottle of copper-containing fertilizers in a 100 liter aquarium, to get into an area that reaches as nearly at concentrations causing shrimp malaise.

No, in no case you should boil it, wash with hot water or solid scrub with the brush! In order to destroy the already biologically treated surface of the root! The previously formed and then destroyed biofilm has now broken down in the aquarium and a new biofilm formed, which leads to increased oxygen consumption in the aquarium. This in turn can cause problems to your animals when the ratio root surface – water quantity the oxygen content is concerning unfavorable.

So please simply wash only in cold or lukewarm water at most. Rests of peat can be carefully removed with a brush.

A commercially available diaphragm or other air pump, air hose and possibly an adjustable T-piece/distributor to connect both air pipes.

No, our rearing box is designed free-floating, i.e. he carries himself (as long as the maximum load is not exceeded).

The length of the air hose then determines the range of motion in the aquarium, so you can use it to the location of the box in the basin determine a bit.

Not with a normal water change. The box floats with the water level (as long as the air hose is long enough…). It only falls dry if the pool is completely empty or the air hose is too short so that it sticks in the air. Make sure that the tubing is long enough and do not allow the tank to run empty….

These are traces of fire clay brick of the kiln. It isn’t harmful. Just wipe it off or brush, should it visually disturb.