denitrate 500 ml — Biomedia Natural Anaerobic Denitrification | Seachem

Seachem denitrate 500 ml is a natural, porous, and economical biomedia whose pore distribution and geometry promote both aerobic nitrification in the first few millimeters of depth and anaerobic denitrification at the core of the medium. It removes nitrates through the same process as live rock, but with significantly greater efficiency by forcing water to filter through its porous structure. Unlike sulfur-based media, it does not produce hydrogen sulfide.

Main advantages

• Natural anaerobic denitrification — removes nitrates like live rock, with superior efficiency
• Dual function: aerobic nitrification (ammonia, nitrites) + anaerobic denitrification (nitrates)
• High surface area and high bacterial density — porous natural material
• No danger from hydrogen sulfide — unlike sulfur-based media
• Never runs out — permanent biomedia, requires no replacement
• Economical — a natural material at an affordable price

Use in reef and marine aquariums

Denitrate works thanks to its porous structure: oxygen is consumed by aerobic bacteria on the surface, creating anaerobic conditions at the core of the media where denitrifying bacteria remove nitrates. Flow rate is critical for denitrification: at flow rates below 200 L/h (50 US gallons/h), denitrate functions as both an aerobic and anaerobic denitrifying filter. At flow rates above 400 L/h (100 US gallons/h), it functions only as an aerobic filter. If high flow rates are unavoidable, use Seachem Matrix or Pond Matrix, which support denitrification at higher flow rates.

Instructions for use

• Rinse off the dust before use
• Place in a cartridge filter, chemical filtration module, box filter, or media reactor
• The flow rate must not exceed 200 L/h (50 US gallons/h) for denitrification.
• After a few days of use, nitrate levels should begin to decrease and stabilize at around 4–5 mg/L
• As long as nitrates remain under control, the product is not exhausted.
• Pre-filter the water with foam or cotton wool before adding the denitrate to prolong its lifespan.

denitrate vs Matrix

Both denitrate and Matrix are biomedia that support denitrification, but with different applications. Denitrate is smaller (gravel-sized) and more efficient per volume for nitrate reduction at low flow rates (less than 200 L/h), making it ideal for use in a dedicated reactor. Matrix is ​​larger (10 mm) and supports denitrification at higher flow rates, making it ideal for use in a canister or sump. Both are permanent and do not require replacement.

Interview

Nitrate doesn't run out but can become clogged with debris and biofilm. Pre-filtering the water upstream with foam or filter floss significantly extends its lifespan. Rinse periodically with aquarium water if necessary.

Available formats

• 100 ml
• 250 ml
• 500 ml
• 1 L
• 2 L
• 4 L
• 20 L
• 100 L

Why choose denitrate from ReefSolution?

The 500 ml denitrate is the ideal starting size for a low-flow denitrification reactor. Combine it with Seachem Matrix in the canister or sump for complete, high-flow biofiltration, and use Seachem Stability to accelerate bacterial colonization. Monitor your nitrate levels with the Salifert Nitrate Test Kit or the Hanna Nitrate Checker.

Frequently Asked Questions

What is the difference between denitrate and Matrix?

The denitrate is smaller and more efficient per volume for low-flow denitrification (less than 200 L/h), ideal for use in a dedicated reactor. The Matrix is ​​larger and supports denitrification at higher flow rates, ideal for use in a canister or sump. Both are permanent biomedia.

What flow rate is needed for the denitrate to remove nitrates?

The flow rate should not exceed 200 L/h (50 US gallons/h) for anaerobic denitrification. Above 400 L/h, the denitrate unit functions only as an aerobic filter (ammonia and nitrites only). A media reactor with a low-flow pump is the optimal setup.

Does the denitrate need to be replaced?

No. It's a permanent biomedia that doesn't run out. It can get clogged with debris — pre-filter the water upstream and rinse periodically with aquarium water to maintain its effectiveness.