Zeolite
Natural porous mineral used as a chemical filter. Removes ammonia from fresh water. In marine aquariums the ZEOvit system is a complete aquarium management method.
Detailed explanation
Zeolites are aluminosilicate minerals with a crystalline structure with microscopic channels. Their ability to exchange ions makes them very useful in aquariums.
In freshwater aquariums, zeolite is used as a chemical filter to remove ammonia. Ammonium ions (NH4+) are exchanged with sodium ions (Na+) present in the structure of the zeolite. It is particularly useful in quarantine or emergency aquariums after an ammonia spike.
Zeolite runs out when all exchange sites are occupied. It can be regenerated by immersing it in a saturated solution of table salt for 24 hours: the sodium displaces the ammonium from the sites. After rinsing the zeolite is ready for new use.
Caution: Zeolite does not work in salt water. The concentration of sodium in seawater immediately saturates the exchange sites, making the zeolite inactive for ammonia.
The ZEOvit system is a complete management method for ultra-low-nutrient reef aquariums. It uses reactorized zeolite (in a flow-controlled reactor) along with bacteria, amino acids and other specific additives. The goal is to keep nitrates and phosphates at very low levels to obtain intense colours in SPS corals. It is a demanding method that requires consistency and precision.
The zeolite in the cake filter must be replaced every 4-6 weeks. It should not be washed with hot water because it loses its crystalline structure.