Unfortunately, we cannot advise on products bought from another source as we do not know how the product was stored or if it is still within it's shelf life. Generally, the gel will work even after it hardens, though, it does work best when it is soft. The gel will dry out quickly if you place it on a porous surface, or if you place it in an area where it is exposed to air currents (heating or cooling vents). You can help avoid these situations by placing the Invict Gold Roach Bait Gel in disposable bait plate stations. Bait Plate Stations are low-profile, economic and easy-to-use plastic stations that hold gel, liquid and granular baits for ants, roaches and other crawling insects. We do recommend cleaning up and replacing any bait that has not been consumed every 2-3 weeks.
Please review our Roach Control Treatment Guide for further tips and information.
