Chemical Products

Our entire line of Stewart Hi-Test® Chemical products for the fishing industry is manufactured by Hocking International Laboratories, using our very strict standards for quality.

Hocking International Laboratories, Inc. is a company that has been dedicated to manufacturing and distributing specialty chemical products, in diverse markets throughout the world, for the last 30 years.  They are well known for their continuing  research  and development to constantly improve their products and maintain quality control.

GTR, Incorporated is the exclusive distributor for the Stewart Hi-Test® line of speciality chemicals for the fishing industry.  All our chemicals in this line are manufactured in the USA by Hocking International Laboratories’ plant just north of San Diego California.

The products available in the Stewart Hi-Test® line of Chemical Products are as follows:

Rust Remover

Rust Converter


Marine Soap Concentrate

Marine Soap SUPER Concentrate
This is same product as Marine Soap Concentrate except it is a version which is 10 times more concentrated.  If you add 50 gallons of water to this product you have the same concentration as a 55 gallon barrel of Marine Soap Concentrate.  This Super Concentrate provides  freight cost savings and for efficient use of limited storage areas.

Heavy Duty Scale Remover

Seiner Set Dye


The Material Data Safety Sheets (MSDS) are available for all the Chemical Products in our line.  If your operation requires any other type of chemical product, we are able to offer a wide range of industrial and speciality chemical product manufactured by Hocking International Laboratories .  Please advise  any special needs or questions you may have.