With the onslaught of the organic carbon source craze, new ideas have been discussed and are now being developed. The solid carbon source idea is one of these. Jean Paul of Reef Interests in the Netherlands that has made this into a practical reality with his NP Biopellets–a bio degradable polymer / organic carbon source media. […]
With the onslaught of the organic carbon source craze, new ideas have been discussed and are now being developed. The solid carbon source idea is one of these. Jean Paul of Reef Interests in the Netherlands that has made this into a practical reality with his NP Biopellets–a bio degradable polymer / organic carbon source media.
Aerobic and some anaerobic growth occurs on the pellets, creating a nutrient rich biomass to be exported
The photos above are from our reef friend and fellow blogger Tatu Vaajalahti, showing the np biopellets in their normal operation and then agitated releasing bacteria (“mulm”) to be skimmed out.
The benefit of a solid carbon source is location. Rather than disperse the growth of bacteria throughout the entire water column it can be relatively localized into one area, which will likely prevent harmful and annoying bacteria to grow in the aquarium–namely Cyanobacteria (Red Slime). This has the power to create a contained nitrate reactor. Aqua Medic has marketed a similar product named DeniBalls for use in their own Nitrate Reactors–however these new NP BioPellets from Reef Interests seem to cultivate much more bacterial growth and quicker.
We have not yet used the NP BioPellets, but that’s not to say we won’t be giving them a try in the future in conjunction with VSV. For more information on these carbon source pellets check out the product description below from Jean Paul:
NP BioPellets are composed of biologically degradable polymers that can be placed in a fluidized filter, or simply in a porous bag in the filtration compartment. The pellets will allow aerobic growth of bacteria which consequently will consume nitrate and phosphate simultaneously. In addition, some anaerobic layers will develop, resulting in additional denitrification. The surplus of bacteria will be skimmed off or eaten by filter and suspension feeding organisms, such as corals and sponges. For this reason, we advise to place the outlet of the pellet filter in front of the protein skimmer. This has the additional benefit of increased gas exchange (CO2-removal and O2-addition).
On average this “solid wodka method” takes a few weeks to give rise to sufficient bacteria to allow nitrate and phosphate levels to drop. The pellets are consumed by bacteria, which is why new pellets need to be added every 3-6 months. This can be seen during inspection of the filter. We advise using 0.5-1 liter of pellets per 500 liter of system volume, and adding 100 ml of pellets every 3-6 months. Of note, these ratios depend on tank conditions and are strongly influenced by feeding regimes and livestock. When heavy feeding is required, we advise to combine the pellets with standard phosphate killers. The reason for this is that most aquafeeds contain higher levels of phosphate than is consumed by bacteria, fish and invertebrates, when compared to nitrogen sources in the food.
Special thanks to Tatu for the photos and information.