What to Expect When You First Start Your Filter: Flushing and Break-In

Customer question

I just installed my new filter and the first water out of it is not what I expected. It looks discolored or tinted, the water is cloudy or milky, there is an odd smell, or it has a funny taste. Did I get a defective filter, or is something wrong with my installation?

Answer

In almost every case, this is normal break-in, not a defect. A brand new filter needs to be flushed before first use. The first water can carry loose media dust, trapped air, and a harmless preservative taste left over from manufacturing and shipping. These clear on their own once you run water through the system as directed.

Here is the short version of what is normal:

Black or gray flecks right after a new carbon stage are loose carbon dust. They flush out, usually within a few minutes for point-of-use systems and longer for whole-house systems.
Cloudy or milky white water that clears from the bottom of the glass upward is trapped air, not contamination. It clears within about a day of normal use.
A tinted or rust-colored first flush from dense media, such as arsenic-reduction media, is normal and can take longer to run clear than carbon.
A break-in taste or odor on new carbon and reverse osmosis (RO) systems is the preservative and dust flushing out. Flush per the system instructions, then discard the first tank or two on an RO system before judging the taste.

The small set of signs that are NOT normal, and that mean you should contact us: discoloration or odor that does not clear after a thorough flush, a sewage-like or septic smell, or any symptoms of illness alongside the water change. In those cases, do not drink the water, and see the support section below.

Crystal Quest has been manufacturing water filtration systems since 1994, and most first-use questions are resolved with a proper flush.

Steps

Flush at first use, by system type:
- Point-of-use (countertop, under-sink, drinking-water systems): run water to the drain until it runs clear, typically several minutes.
- Whole-house systems: open a nearby cold tap or flush valve and run to drain until clear. This takes longer than a point-of-use system because of the larger media volume.
- Reverse osmosis (RO): flush the membrane per the system instructions, about 30 minutes, then let the storage tank fill and discard the first tank or two before judging taste.
If you see black or gray flecks: this is loose carbon dust from a new carbon stage and is normal for the first flush. Keep running to drain until the water is clear. If dust still appears after a full flush, re-seat the cartridge and flush again.
If the water is cloudy or milky white: this is trapped air. Fill a glass and watch it. If it clears from the bottom upward, it is air, not contamination, and it clears within about a day of normal use.
If the first water is tinted or rust-colored from a dense-media stage, such as an arsenic-reduction cartridge: this is normal and can take longer to run clear than carbon. Flush until the water is clear.
Sanitize the storage tank before putting it into service. A tank that was not sanitized before installation can give the water an off taste or odor. Tanks should be sanitized before being placed in service.
On an RO system, discard the first tank or two after flushing. The first fills can carry a break-in taste; the water improves once the system has cycled.

Safety / before you start

Before any work on the system, shut off the feed water supply and relieve pressure at a nearby faucet or the system valve so the lines are depressurized.
Do not drink the water if you notice a sewage-like or septic smell, or if anyone has symptoms of illness. Stop using it for drinking and contact support.
If discoloration or odor will not clear after a thorough flush, have the water tested before drinking it, and contact support.
A normal break-in taste, light cloudiness from air, or carbon dust on the first flush are not safety concerns and clear with flushing.

When to contact support

Reach out to us if, after a thorough flush, you see any of these. These are NOT normal break-in:

Discoloration that does not clear after a full, thorough flush.
An odor that does not clear after flushing, especially a sewage-like or septic smell.
Any water change paired with symptoms of illness.

In these cases, do not drink the water, consider a water test before drinking, and contact support. Troubleshoot and flush first; Crystal Quest resolves true defects per the system warranty.