Purigen， 4 L / 1 gal.</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>Unparalleled capacity to remove organic waste controlling the release of ammonia nitrite and nitrate</li><li>Polishes water to an unparalleled clarity</li><li>Regenerable with household bleach</li><li>Minimal impact on trace elements; significantly raises redox</li><li>250 milliliters treats 250 gallons</li></ul></div></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br><img src='http://ecx.images-amazon.com/images/I/51JHUu9GJiL.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/31W4usUcPbL.jpg' noproxy></br>