Tidal Clear® is our family of chitosan and biopolymer hybrid solutions. We begin with the power of high molecular weight chitosan, and make it available in ready-to-use liquid solutions that are optimal for stormwater and wastewater.

Incorporating chitosan into your water treatment system reduces operating costs, increases throughput, and enables sludge upcycling.



Runoff from construction sites and farms drains into local bodies of water and is a major source of suspended solids, heavy metals & minerals, hydrocarbons, and other pollutants that chitosan binds to.


The demand for safe & clean ways to treat wastewater from industrial factories, mining operations, and power plants will only continue to grow. Incorporating chitosan is not only good for the environment, but also lowers operating costs and increases system flow rate capacities.


Food Processing

Because chitosan is safe and nontoxic, the flocs or “sludge” generated in treatment can be upcycled as a protein, lipid, and/or dye concentration, adding economic value to wastewater byproducts. The US Food Drug Administration (FDA) approves the use of chitosan in these processes.

The versatile, non-hazmat, natural & biodegradable biopolymer flocculant & coagulant.


Chitosan is an ideal eco-friendly flocculant for water clarification applications due to its ability to bind to a variety of organic and inorganic particulates [1].

Removal of suspended solids, dyes, heavy metals, and other pollutants is facilitated with chitosan in solution at acidic, neutral, and alkaline pH conditions [2,3].


Aggregation and flocculation by chitosan occur because of the unique pH-sensitive and strong hydrophilic nature of chitosan. Chitosan can then be removed via filtration or sedimentation; leaving clarified water behind without any residual toxic chemicals [4].

Adding chitosan lowers costs and increases throughput:

  • Reduces the amount of inorganic metal coagulants used by 70% to 100%.

  • Since metal coagulants lower pH, using chitosan reduces or eliminates this drop in pH and eliminates the need for handling caustic.

  • Lowers Total Dissolved Solids (TDS) compared to traditional metal coagulants.

  • Lowers turbidity faster than metal coagulants alone.

  • Increases filterability & floc strength so you can increase flow rates with your existing infastructure.

  • Greater efficiency & filterability + lower TDS = higher flow rates and reduced wear & tear on equipment (RO, nanofiltration, or other).

  • Our high molecular weight chitosan solutions have a much lower application rate than metal coagulants – as much as 50X lower in many cases!

  • Lower solids volume + higher filter run length = longer run cycles, less backwashing, and less sludge volume.

  • Enables sludge upcycling for fertilizer, animal feed, protein recovery, etc.

  • Non-hazmat makes it easier and safer to handle and lowers your transportation costs.

Chitosan vs. the Competition:

Other Uses for Chitosan in Water Treatment

The removal of microorganisms from suspension presents a challenge in beverage manufacturing, algal biomass production, and water treatment. Chitosan has been shown to bind directly to the outer cell wall of microorganisms in a range of pH conditions [5,6].

Jar Testing Made Easy

  1. Ensure the water sample is thoroughly mixed and measure the initial turbidity.
  2. Pour 1000 mL of the water sample into a beaker for each treatment option and one additional beaker for the control. Treatment options may include varying chemicals or dosage rates depending how many tests you aim to run at once.
  3. Prepare a stock dilution of the chitosan solution. Effective dose rates are highly variable. Typical stormwater requires 40-150 ppm. Measure 1 part Tidal Clear into 99 parts DI water. Every 1 mL of this stock solution will deliver a 10 ppm dose of treatment chemical into 1000 mL of stormwater. Add diluted flocculant up to the desired PPM.
  4. Set the mix rate, mix time and settling time to mimic field conditions as much as possible. Add the treatment chemicals during the “slow mix speed” interval to all beakers except the control. 
    1. If conditions are unknown, use these settings: High mix speed (~250 RPM) for 1 minute → Slow mix speed (~50 RPM) for 3 minutes →  Slow agitation (~20 RPM) for 5 minutes →  Settling for 10 minutes
  5. After settling is complete, measure the turbidity of a sample drawn from one inch deep in the center of each beaker. 
  6. Increase or decrease dosage as necessary.

[1] Guibal, Eric, et al. “A review of the use of chitosan for the removal of particulate and dissolved contaminants.” Separation science and technology 41.11 (2006): 2487-2514.
[2] Bhatnagar, Amit, and Mika Sillanpää. “Applications of chitin-and chitosan-derivatives for the detoxification of water and wastewater—a short review.” Advances in Colloid and Interface Science 152.1 (2009): 26-38.
[3] Guibal, Eric. “Interactions of metal ions with chitosan-based sorbents: a review.” Separation and purification technology 38.1 (2004): 43-74.
[4] Renault, François, et al. “Chitosan for coagulation/flocculation processes–an eco-friendly approach.” European Polymer Journal 45.5 (2009): 1337-1348.
[5] Divakaran, Ravi, and V. N. Sivasankara Pillai. “Flocculation of algae using chitosan.” Journal of Applied Phycology 14.5 (2002): 419-422.
[6] Cheng, Yu-Shen, et al. “The impact of cell wall carbohydrate composition on the chitosan flocculation of Chlorella.” Process Biochemistry 46.10 (2011): 1927-1933.