How to Clean a Water Softener Brine Tank (Easy DIY Tips)

To clean a water softener brine tank, put the softener in bypass, scoop out the salt, remove the leftover water and sludge, scrub the tank with dish soap and water, then sanitize it with a weak bleach solution (about 1/4 cup of unscented household bleach in 2 to 3 gallons of water). Rinse well, reassemble, add fresh salt and run a manual regeneration. Plan on about an hour, once a year or whenever you see sludge, a salt bridge or mold.

A clean brine tank matters because it makes the brine that recharges your resin. When the tank is full of sludge or a crusted salt bridge, the brine gets weak, regeneration falls short and hard water comes back. If your tank is filling too high, see why a water softener overflows first.

What a Brine Tank Does (and Why Water in It Is Normal)

The brine tank is the shorter tank or cabinet that holds the salt. Water sits in the bottom and dissolves salt into a strong brine. During regeneration, the control valve draws that brine through the resin tank, where it strips off the calcium and magnesium the resin has collected and recharges the beads with sodium. The valve then refills the brine tank with fresh water for next time.

So yes, water in the salt tank is normal. Depending on the design, you may see several inches of water at the bottom all the time, or the tank may refill only shortly before regeneration. What is not normal is water rising to the top, or a tank that never refills. See is it okay if the brine tank gets low on water? and troubleshooting a brine tank that won’t fill .

Signs Your Brine Tank Needs Cleaning

• Sludge or a muddy layer at the bottom. This is insoluble material from the salt, most common with rock salt and some solar salt.
• Black or dark specks floating or settled in the brine. Usually impurities from the salt. Dark slime on the walls is more likely bacteria or mold.
• Orange or rust-colored residue , a sign of iron in your water.
• Tan or amber beads in the brine tank. Those are resin beads, and they point to a problem in the resin tank or valve, not the brine tank. See what to do if you find resin beads .
• A hard crust of salt with an empty space beneath it (a salt bridge), or a mushy layer at the bottom (salt mushing).
• A musty or rotten-egg smell from the tank, or hard water even though the salt level looks fine.

What You Need

• Bucket, scoop and a wet/dry shop vacuum
• Mild dish soap and a long-handled brush or sponge
• Unscented household bleach (plain, not splash-less or scented)
• Rubber gloves and eye protection
• Fresh softener salt (evaporated pellets or solar crystals)
• Your softener’s owner’s manual, so you know how to start a manual regeneration

You don’t need a special "brine tank cleaner." Soap, water and dilute bleach handle the tank itself. Products sold as resin or iron cleaners are a different thing: they are added so they pass through the resin during regeneration, which helps if iron is fouling the resin. If that is your problem, see cleaning the resin bed .

Tip: Clean the tank when the salt is low. There is less to scoop out, and you won’t waste much salt.

Step-by-Step: How to Clean a Water Softener Brine Tank

1. Put the softener in bypass. Turn the bypass valve so water flows around the softener. Unplug the control valve if your manual recommends it.
2. Remove the salt. Scoop it into a clean bucket. Dry, clean pellets can go back in later; throw out mushy or dirty salt. Break up any salt bridge gently with a broom handle. Don’t jab the tank walls or the brine well.
3. Remove the water and sludge. Use a wet/dry vacuum to pull out the remaining brine and the sludge at the bottom. On a light cabinet unit you may be able to tip the tank into a floor drain once you disconnect the brine line.
4. Take out the removable parts. Lift out the salt grid or platform if your tank has one, and the brine well cap. Note how the float assembly is set before touching it. Don’t bend the float rod or change its height.
5. Scrub with soap and water. Use a few gallons of warm water with a squirt of dish soap. Scrub the walls, bottom, salt grid and inside the brine well. Rinse and vacuum out the dirty water.
6. Sanitize. Mix about 1/4 cup of unscented bleach into 2 to 3 gallons of water, pour it in, scrub the walls and let it sit for about 15 minutes. Never mix bleach with vinegar, ammonia or other cleaners.
7. Rinse thoroughly. Rinse two or three times with clean water and vacuum it out until there is no bleach smell. Check that the brine line, float and screen at the bottom of the brine well are clear.
8. Reassemble and refill. Put the grid and brine well cap back. If your tank normally holds water, add a few gallons, then fill salt to about half to two-thirds full. See how much salt to put in your softener .
9. Return to service. Take the softener out of bypass, plug it back in and start a manual regeneration. That draws fresh brine, flushes the system and lets the valve refill the brine tank to its normal level.

Want to also sanitize the resin tank? Follow your owner’s manual and use a product made for softener sanitizing. Repeated bleach doses through the resin can shorten its life. Our guide to using bleach to sanitize a brine tank covers the do’s and don’ts.

Fixing the Most Common Brine Tank Problems

Salt bridges

A salt bridge is a hard crust that forms above the water line. The salt looks full, but there is an air gap underneath, so no brine is made. Humidity, overfilling and some salt types make it worse. Break it up gently, keep salt no more than about two-thirds full, and use pellets or crystals made for softeners. More in how to prevent salt bridging .

Salt mushing

Mushing is a sludge of recrystallized salt at the bottom of the tank that can block the brine well and the brine pickup. It is more common with low-quality pellets. Scoop it out, clean the tank and switch salt. See what is salt mushing in the brine tank?

Mold, slime or bad smell

Mold in a water softener brine tank usually grows on the walls above the brine, where it is damp but not salty enough to stop growth. The cleaning and bleach steps above take care of it. Keep the lid on and the area dry. If the smell is rotten eggs, the cause may be in your water rather than the tank; see brine tank smell causes and fixes .

Orange residue from iron

Rust-colored residue means iron is in your water. The SoftPro Elite is rated to handle up to 3 ppm of iron; above that, an iron filter such as the SoftPro AIO Iron Master should go in front of the softener so iron never reaches the resin. Browse our iron filters for well water or read how to flush iron buildup from your system .

How Often Should You Clean a Brine Tank?

For most homes using evaporated salt pellets, a full cleaning every year or two is plenty. Homes using rock salt, or with iron or high salt use, may need it once or twice a year. The easiest habit: look inside every time you add salt. If you see sludge, a crust, slime or color, clean it. If everything looks clean and your water is soft, leave it alone.

Tips to Keep Your Brine Tank Clean Longer

• Use cleaner salt. Evaporated pellets leave the least residue, solar crystals are next, and rock salt leaves the most. See choosing the right water softener salt .
• Don’t overfill. Keep salt at about half to two-thirds full and add it more often instead of topping off to the brim. That cuts down on bridging. Here is how to check your salt level .
• Keep it dry and closed. Humid spaces and an open lid promote bridging and mold. A dehumidifier helps in a damp basement.
• Keep the softener set right. An incorrect hardness setting means extra regenerations and more salt through the tank. Our full water softener cleaning guide covers the rest of the system.

For the mistakes people make most often, like using the wrong bleach or skipping the rinse, read brine tank cleaning tips homeowners miss .

Frequently Asked Questions

Keep Your Softener Working Like New

A clean brine tank is one of the cheapest ways to keep soft water flowing. Clean it when you see buildup, use good salt, keep the level at half to two-thirds and set the softener to your actual hardness. If your system is aging or you are fighting constant problems, compare our water softener systems ; every system ships free in 1 to 3 business days with a 6-month money-back guarantee.