En vrac:
Objectives : aesthetics, nitrate control, or plankton production??
Strong water movement in the aquarium is the number one key to success with long-term healthy DSBs.
Avoid adding predatory fishes or corals to DSB systems for many months to allow adequate populations of infauna to develop.
I recommend sand grains under 2 mm in size for DSBs. Media that is larger than 2 mm can be used, but deeper beds and stronger water flow will be required to make it work successfully. Large sand grains allow excessive solid matter to penetrate deeper and faster and can lead to the problem that critics cite with DSBs becoming “nutrient sinks.” That said, a mix of large and fine grain sizes together can work if there is enough fine sand
My recommendation is most always to keep your DSB remotely.
The typical RDSB application for home-sized aquariums (under 800 liters) is a large bucket full of sand (maybe 25 kg of fine sand in a 20 liter bucket) that has a supply of filtered water on a continuing path in the aquarium system. Some folks simplify it even further by sitting their RDSB bucket in an unlit sump and gravity feed water from a display or refugium above… or even a tee off of the sump pump manifold. The sump RDSB can then gently spill over the sides of the bucket into the open reservoir. It is quite simple and effective for mainataining nitrates below 10 ppm.
However you choose to install an inline (R)DSB, you can estimate that approximately 25 kg of fine sand
Calcite DSB
advantages: commonly available, moderately priced, wide range of grain sizes
disadvantages: very little buffering ability over 7.6 pH
Silica DSB
advantages: very inexpensive from industrial sources
disadvantages: no buffering, limited sizes
Aragonite DSB
advantage: optimal shapes (oolitic and very fluid), excellent buffering pH, and mineral supplying
disadvantage: generally more expensive and less available than silica or calcite
We do know that good denitrification is less likely (but not impossible) to occur in shallow sand beds (less than 3”/7.5 cm), and with course sand. Some of the difficulties and criticisms of failed DSBs may be fairly attributed to such intermediate sand depths (1-3”/25-75mm) where the substrate was neither deep enough for efficient denitrification, nor shallow enough for thorough nitrifying activities. This condition is mitigated by the all too common lack of adequate water flow in some marine aquaria.
En dessous, figure 8, un refuge sombre avec des bio-balles de 9 cm. Oui c'est un bio-média. Il est très grand et a très peu de surface. On l'utilise pour la croissance des éponges, et des vers tubicoles, parmi tant d'autres. Vous y trouverez des crevettes, crabes, cocepodes, isopodes, nudibranches et bien d'autre bestioles. Ce type particulier de refuge pour animal peut-être utilisé pour nourrir des coraux, des éponges qui ne supportent pas la lumière, "Sun polyps" et d'autres créatures intéressantes que l'on observe habituellement pas car elles se situent à la base des pierres vivantes. Toutefois, j'ai trouvé que ce type de refuge était très intéressant pour la nature atypique de ses habitants.----------------
Dans ce mix de copier/coller du net, il y a l'explication de mon crash de mon bac et il y a les éléments pour mon projet futur...
To be continued.
W!m06.
