Solid Vodka Dosing is a relatively new concept from a company called NP Biopellets. The carbon source-infused polymer beads are meant to grow bacteria in layers that could usher in a revolutionary new way to manage nutrients in aquarium water. If it works. We say “if” because although the idea and principles for solid vodka dosing are sound, there has been very little real world testing for the use of Solid Vodka Dosing in home aquaria. To be clear, these nutrient reducing pellets have nothing to do with vodka but the term reflects the regular vodka dosing which many reef aquarists have been using for years now. The Solid Vodka Dosing concept is reminiscent of the good ole Nitrex media that has been in use for freshwater aquariums for decades. According to the manufacturer NP Biopellets, the biodegradable polymer pellets can be placed in a canister or fluidized bed filter. 
Carbon from the Biopellets will fuel the growth of nitrogen and phosphate consuming bacteria that colonize the pellet in anaerobic and aerobic successions.
The manufacturer of the NP reducing biopellets has a “how it works” page that is lackluster in details of what really drives the solid vodka dosing method. The only real details are that the media takes 2-4 weeks for bacteria to colonize in any siginificant number (which just about anyone can deduce from a basic understanding of bacterial colonization) and that 1 liter of the NP reducing Biopellets is enough media to treat around 500 liters/ 130 gallons of aquarium water. The biopellets should be placed in an area of high flow to prevent the buildup of hydrogen sulfide and to encourage strong bacterial colonization. Using this lightweight media in a fluidized bed scenario might encourage the breaking off of bacterial film that will in turn feed the aquarium corals a-la Zeovit reactor. Whether this home made marine snow is enough to feed and sustain difficult species is totally unknown.
We’re going to go ahead and call out the dealer for having very little information and concrete results for how well this solid vodka dosing product performs. There are some reports that the system is particularly suited for reducing nutrients in heavily fed non-photosynthetic aquaria but so far the only success has been with relatively easy to keep species such as Rhizotrochus and Tubastrea species. Needless to say, with all the attention reef aquarists have placed on carbon dosing reef tanks to reduce nutrients eiter through the use of ethanol or vodka, we are very excited about the solid vodka dosing approach to localizing bacterial colonies on a carbon infused substrate. Although the food is there for bacteria to grow, the biopellets are a simple food substrate and we will still likely use the biopellets with some kind of targeted bacterial cultures. This technique may be a standalone gateway to true oligotrophic reefing but we feel that it might be complimented by other bacteria stimulating techniques such as Vodka Dosing, Prodibio or Zeovit. A liter of NP-reducing Biopellets costs 50€, about $75, before shipping from the EU and it can be ordered from the NP biopellets website.
