Bio S — Nitrifying Bacteria for the Reef Aquarium Nitrogen Cycle 10 ml and 50 ml - Aquaforest

Aquaforest Bio S — nitrifying bacteria for reef aquarium nitrogen cycle

The Bio S is Aquaforest's liquid nitrifying bacterial supplement, formulated to accelerate and stabilize the nitrogen cycle on a new marine aquarium or after a significant water change. It contains selected bacterial strains that speed up the breakdown of toxic organics and ammonia, greatly shortening the wait time on a new reef tank. Available in 10 ml and 50 ml.

The 10 ml format seeds several nano-to-mid tank volumes — the 50 ml is the economy format for larger tanks or regular use. Paired with Bio Sable and Life Bio Fil, it makes up Aquaforest's fast biological startup strategy.

Bio S startup use

• Official dose: 1 drop per 100 L (27 US gal) of tank water per day, for the first two weeks after setup.
• Established tank: add Bio S after each significant water change to offset the diluted bacterial loss.
• Compatibility: can be combined with other nitrifying bacteria (Life Bio Fil) without antagonistic effect.
• Storage: keep cool after opening, avoid direct sunlight exposure.

What Bio S brings to the tank

• Nitrifying bacteria (Nitrosomonas and Nitrobacter) — NH3 → NO2 → NO3 oxidation.
• Accelerated breakdown of dissolved organic compounds.
• Ammonia spike reduction during initial cycling.
• Biological support for bacteria hosted in live rock and sand.

Specifications

• Brand: Aquaforest (Poland)
• Formats: 10 ml and 50 ml bottles
• Type: liquid nitrifying bacteria
• Compatibility: all marine aquarium types, initial cycling and post-water-change

Why choose Aquaforest at ReefSolution

• Bio S 50 ml — the economy format for larger tanks or regular use (also sold on this page via the Format option).
• Bio Sable 7.5 kg — the seeded live sand that pairs with Bio S at startup.
• Life Bio Fil — the biological bacterial media that extends Bio S action in the filter.

Frequently asked questions

Can Bio S fully replace a slow cycle?

Bio S accelerates cycling but doesn't replace the biomass needed to support final livestock. On a reef tank, still plan 2-3 weeks of bacterial development before adding the first inhabitants, with NH3 and NO2 tests below detection threshold for at least 5 consecutive days.

How long does a bottle last?

At 1 drop/100 L/day (0.05 ml), a 100 L tank uses 0.05 ml/day: the 10 ml bottle covers 200 days, the 50 ml covers 1000. On a 300 L tank at startup, the 10 ml drops to 66 days — well over the two critical weeks.

Should I keep dosing Bio S after initial cycling?

No — after cycling, the bacterial population self-regulates on live surfaces. Bio S becomes useful again after a big water change, after a medication treatment that impacted the flora, or after moving the tank.