Seachem Ammonia Alert is a continuous ammonia monitor that mounts inside your aquarium and warns you the moment toxic free ammonia begins to climb. Unlike bottled kits you have to run by hand, it reads your water around the clock and changes color within minutes, so a cycling crash or an overfeeding never sneaks up on you. It works in both freshwater and saltwater and pairs naturally with the rest of our water testing gear and water care. What It Does Watches the toxic form of ammonia. It detects free ammonia (NH3), the form that actually burns gills, and ignores harmless bound ammonium (NH4+), so you are not alarmed by a number that does not matter. Always on, no testing required. No reagents, no test tubes, no counting drops. Glance at the tank and read the color. Reacts quickly. The sensor responds within minutes and tracks changes continuously as your water shifts. Lasts over a year. A single sensor keeps working for more than 12 months of continuous use. Freshwater and saltwater. Accurate in both, and unaffected by pH or chloramine. Reading the Colors The sensor sits against a printed reference scale. Yellow means safe, with free ammonia below 0.02 ppm. As free ammonia rises the disc shifts toward green and blue, moving from the Alert zone into Alarm. Any color past yellow is your cue to act: confirm with a full test kit, run a water change, and dose an ammonia detoxifier. How to Use Peel the backing and mount the sensor inside the tank, fully submerged, where you can see it easily. Allow up to a few hours after installation for the reading to fully stabilize. Check it during daily feeding. Re-test with a liquid kit any time it leaves the yellow zone. Replace after about a year, or if the color stops responding to changes. Specifications Product Continuous ammonia monitor Measures Free ammonia (NH3), the toxic form Range Safe below 0.02 ppm, then Alert 0.05, Alarm 0.2, and Toxic at 0.5 ppm Water type Freshwater and saltwater Service life More than 1 year of continuous use Reagents None required Brand / origin Seachem, made in the USA Works With Your Detoxifier Because Ammonia Alert reads only free ammonia, dosing a conditioner like Seachem Prime or Seachem AmGuard will visibly lower the reading as it locks ammonia into its non-toxic form. That is exactly what you want to see, and it is something ordinary total-ammonia kits cannot show you. Recommended Pairings Seachem Alerts Combo Pack (Ammonia & pH), add continuous pH monitoring alongside ammonia in one holder. Seachem Prime, detoxify ammonia and nitrite instantly when the alert warns you. Seachem AmGuard, a dedicated emergency detoxifier for larger ammonia spikes. Seachem Stability, build and keep a strong biofilter so ammonia never climbs in the first place. Fritz Ammonia Test Kit, confirm an exact number any time the alert leaves the safe zone. FAQ How is this different from a regular ammonia test kit?A test kit gives you a single number the moment you run it, and it usually reports total ammonia. Ammonia Alert stays in the tank and continuously shows the toxic free ammonia only, so you catch a problem between tests instead of after the damage is done. Will my water conditioner make the reading drop?Yes, and that is a good thing. Detoxifiers convert free ammonia to a bound, non-toxic form, which is the form Ammonia Alert is designed not to count. A falling reading after dosing means the product is working. Does it work in a saltwater or reef tank?Yes. It is accurate in both freshwater and saltwater and is not thrown off by pH or salinity. How long does it last?More than a year of continuous use. Replace it when the color no longer responds, or roughly once a year to stay safe.
