Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
I think I would wrap a piece of twist-tie or the smallest zip-tie around the split chopstick. As it shrinks and swells the card will get loose. Even a rubber band, though they will rot with time.
I still use my Pet Smart card for its original purpose, but the Pet Co card has been an algae scraper for so long all the color is wearing off.