Unlike the toilet bowl, the tank should never come in contact with dirty water. However, it can still get a little grody in there over time—possibly from a metal (flapper) chain that’s rusted, hard water stains on the ceramic, mineral buildup, or even smelly bacterial deposits.

If someone once put a brick in the tank to save water, you may also be dealing with crumbled sediments gathered at the bottom of the tank, and possibly even dropping into the toilet bowl when you flush.

(Pro tip—if you want to save water for each flush, use a filled and sealed plastic jug or a buy a “tank bag” instead of a brick.)

If your toilet tank is due for a semi-annual cleaning, here’s how to do it:

1. Empty the Tank

Shut off the water to your tank (typically there’s a twistable shutoff valve in the wall near the bottom of the toilet.) Flush a few times to empty the tank.

2. Apply elbow grease

In some cases, a simple scrubbing is all the tank needs to remove stains. A long-handled scrubbing brush can work wonders—you don’t want to be doing this tedious work with a soft sponge. You may, however, want to use a sponge to help wipe out any brick sediment at the bottom of the tank.

3. Use vinegar for mineral deposits

Still can’t get those stains up? You may need to turn to a simple chemical solution—vinegar. You can fill your tank with plenty of vinegar (or a strong vinegar solution, if you don’t have gallons of vinegar on hand) and let it soak—up to overnight if the buildup is especially bad.

Can’t stand the smell of vinegar? You may try lemon juice instead. Bleach is also an option, but it’s bad for the environment and can be rough on your toilet tank’s hardware, so we don’t recommend it except in extreme cases.

Note: If your home runs on a septic system, SKIP THIS STEP and go light on #4 as well. Flushing antibacterial substances will cause major problems with your septic tank.

4. Disinfect

You can use a commercial cleaner (read the label carefully!) or a put together a natural cleaner. Spray the inside of the tank and let sit for a few minutes in order to kill any lingering bacteria.

(If you’ve already used vinegar, you don’t need to do this step, since vinegar will have already done the job).

Warning: Do not follow up vinegar or ammonia-based cleaners with anything containing chlorine bleach, oxygenated bleach, or hydrogen peroxide. This can produce toxic fumes or caustic solutions that can hurt you.

5. Wipe down the tank mechanisms

Use a sponge and a small amount of diluted cleaner to disinfect the float, flapper, chain, valves, and tubes. And if you notice anything starting to look worn, now’s a great time to replace parts to avoid having to fix a running toilet down the road.

6. Refill the tank

Turn the water back on and flush a few times to refill the tank. You should be set for another six months or so!

What about “drop-in” style cleaners?

You may have seen blue or white tablets on the market that claim to keep the tank clean. On the one hand, these can help keep the water disinfected (in case you’re having an issue with bacterial buildup). On the other hand, they can occasionally break down the rubber components of your toilet—such as your flapper—meaning you’ll have to fix your toilet more often.