Can dosing organic carbon be useful in skimmerless ULNS started with a dry rock?

dk2nt9 · Dec 1, 2021

Just saw in another thread recommendation to dose organic carbon for a tank that started with a dry rock, as one of the steps for increasing biodiversity.

From what i have read before, looks that this is used for systems with a skimmer for harvesting bacterial biomass, kind of nutrients export.

My small tanks have no excess of nutrients, but they are based on a dry rock, LR was not available during pandemic. They are fishless, have to dose nitrates and phosphates to keep them in detectable range. Can dosing organic carbon be useful for this kind of system? If yes, what low end form of it: Reef Plus, AcroPower or else.

Nano sapiens · Dec 1, 2021

Carbon dosing (NoPox, vinegar, vodka, etc.) is typically used to bring down high NO3 (and PO4 to a lesser degree) by encouraging bacteria to grow and assimilate these 'nutrients'. The excess bacteria then needs to be removed, typically via protein skimming. 'Bacteria in a bottle' products are often added in the hopes of adding bacteria biodiversity, but just be aware that the types of bacteria present are very limited (nothing like the diversity that's in/on live rock).

With all dry rock only, you have an extremely limited microbial community in your tank (a diverse microbial community is necessary for a successful/healthy reef aquarium). Live rock, live sand (from aquaculture in the ocean or from someone's healthy reef aquarium) or 'macro/micro life starter kits' from GARF or IPSF will also help. You will also get some additional diversity from coral and it's attachments and even the fish that you add.

dk2nt9 · Dec 2, 2021

Thank you, thought so. In Canada at the time of pandemic this is a bit more complicated, have to use clumps of chaeto, live phyto and pods, old frags from LFS to get some life on them.

Randy Holmes-Farley · Dec 2, 2021

There are a variety of good reasons to dose organic carbon, but I do not see a "benefit' to any increase in bacterial diversity it creates (if any). it may actually reduce it.