The Baleen Max Pre-Filter helps with removing metals, calcium, or any other organic compounds from your fill water to ensure the cleanest and clearest water. This makes balancing easier for later purposes. with the MAX FE ionic change calcium becomes inactive and metals aren’t able to stain your pool/hot tub. This pre filter attaches to any standard size garden hose for ease of access. You can use this filter for up to 10,000 gallons of water.