Review on Zoo Med Carbon Bag for 501 Turtle Filter: Enhance Water Filtration with Carbon Media by Brandon Harding

Filter 501 works! I have a 50 gallon tank of about 1/2 inch with a 6 inch red tube spool. All was well at first, but as The Flash (that's his name) neared the 6-inch mark, the carbon bags couldn't keep up. . I cleaned the aquarium 2-3 times a week and struggled to keep the water clean even at this rate. This slime kept collecting in the filter, and I changed the charcoal bag weekly. After searching the internet for a solution, I found something. API makes a product called AmmoCarb, these are granules of charcoal designed for the same purpose as the Zoo Med charcoal bag, IT ONLY WORKS! You need to purchase a small cloth "filter bag" (available in the aquarium section of your local pet supply store for less than a dollar), and you simply refill this AmmoCarb bag and place it where the Zoo Med bags fit target. You clean the filter. I'm amazed how well it works. I bought a 40 ounce container for about $12. Now I clean my aquarium about every 8-10 days, more maintenance than necessary. The flash is happy and so am I! Hope this helps someone struggling with similar issues.