The following article originally appeared September 11, 2019, via Silicon Prairie News.

Ames, Iowa based Gross-Wen Technologies (“GWT”) filed paperwork with the SEC on Tuesday that it had raised an additional $1.25 million dollars.  The company which provides revolving algal biofilm system (“RAB”) to cost-effectively recover nutrients such as nitrogen and phosphorus from wastewater.

GWT primarily serves customers (usually cities) that own wastewater treatment plants, and many are small towns seeking ways to manage wastewater cost effectively.  Through various reports, founder, Martin Gross explained why helping small towns, such as Slater, Iowa was so important to his company.  Through GWT, Gross estimated that the company could comply not just with current regulatory standards but ones that are evolving and are likely to become stricter.  More than just better compliance, GWT offers a solution that can help small cities, such as Slater, save as much as 33% of their projected budget for wastewater treatment.

The RAB product helps treat wastewater, is more effective, and actually costs less than other options.  According to the website, “the RAB system uses vertically oriented conveyor belts that grow algae on their surface. While the algae grows it ‘eats’ nitrogen and phosphorus from the wastewater. It also uses Carbon Dioxide from the atmosphere and sunlight to rapidly grow algae biomass. The algae produced during this process is a revenue stream for our customers and can be used to make fertilizers, bioplastics, and biofuels.”  This resulting by-product is a pelletized product that can be sold separately as a fertilizer.

The company has raised money in the past – including $2 million from Doerfer (a Waverly, Iowa based strategic investor in equipment) in the summer of 2018.  The firm is also the product of the commercialization of multiple Small Business Innovation Research grants in 2016 and 2017 (

The firm was founded by Dr. Martin Gross and Dr. Zhiyou Wen in 2016.  The founders utilized the services of the Iowa State Startup Factory and is a member of the Ag Startup Engine.  In discussing their reasons for forming a company that dealt with water quality and treatment, Gross stated the importance of building solutions for small towns.  That focus helped Gross identify Slater, and other similarly situated cities.  As someone born and raised in small town Iowa, Gross stated that solving real problems for small towns is an important mission for GWT.

The firm won the Prometheus Award for a Startup in Iowa from the Technology Association of Iowa in the Spring of 2019.   This award is given to a promising new company emerging on the scene during the previous year.

For more information about GWT, check out their website at

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