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If you have ever owned a fish tank, you know the horror of waking up in the morning to discover that your fish have died overnight from ammonia poisoning. While it’s always unpleasant to deal with, ammonia poisoning can easily be avoided by following these six simple tips for reducing ammonia in a tropical fish tank.

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Top 3 Mistakes Newbies Make Setting Up Their Fish Tank.

Tropical Fish TankTropical Fish Tank
Neale Monks at the English-language Wikipedia, CC BY-SA 3.0, via Wikimedia Commons

1. Regular Maintenance

The number one thing you can do to reduce ammonia in your tropical fish tank is regular maintenance. This means cleaning up uneaten food, waste, and detritus from your aquarium.

The more you remove these things, and keep a clean aquarium for your fish, the less ammonia will accumulate. Some fish are especially finicky eaters or produce more waste than others; with some species of tropical fish (like goldfish) cleaning up after them isn't enough.

2. adding live Plants

Using live plants can help reduce ammonia in tropical fish tanks because it encourages healthy bacterial growth.When these bacteria break down organic material and waste products, they transform ammonia into nitrite and then nitrate.

While nitrate is still an irritant for tropical fish, it is easier on their gills than ammonia, making it safer for them to swim around.

Adding live plants also gives your fish something to hide behind when they feel stressed out or scared, keeping them calmer and giving you a cleaner tank.

3. Remove any uneaten food from the Tank

The biggest ammonia culprit is leftover food. Even if you feed your fish only once a day, don’t forget to clean out their tank before bedtime.

The longer an uneaten meal sits at room temperature, the more it breaks down and begins producing ammonia.

If you notice leftover food from your last feeding lying around after you wake up, that’s probably not good for your fish or their environment.

For better health and balance in your tank, remove any uneaten scraps before they have time to decompose.

4. Change a little water often

Water changes are necessary if you want to keep your fish healthy and reduce ammonia levels. While it’s tempting to change 100% of your water every week, doing so is a definite NO-NO. (As this will remove beneficial bacteria from your fish tank.)

Instead, only change 20% of your tank’s water each week.

More frequent changes create an environment where ammonia is likely accumulating faster than bacteria can break it down, resulting in higher concentrations of toxic ammonia in tropical fish tanks.

However, with more frequent smaller water changes, these toxic concentrations will occur much less frequently.

5. Feed Less, change more frequently

If you have tropical fish and you’re an occasional fish owner, chances are, at some point, your aquarium will contain too much ammonia.

If left untreated, it can lead to sick or dead fish. The main culprit is overfeeding. Feeding your fish even once per day can cause dangerous ammonia spikes if they don’t immediately eat what they’ve been fed.

To keep your tank healthy, stop feeding and make sure any uneaten food has been removed within 15 minutes of serving it.

6. Add Beneficial Bacteria To Your Tank

Bacteria are one of nature’s most efficient tools. If you want to reduce ammonia in your tropical fish tank, adding beneficial bacteria is an excellent way to do it.

One of the best-known sources of beneficial bacteria is Aqua-safe. Add it directly into your aquarium. To reduce ammonia effectively, you should perform monthly water changes using a solution of 50% water from your tank and 50% tap water.

You can also purchase test kits that will monitor ammonia levels for you so that, over time, you can learn how many days before testing is appropriate for your aquarium.


For tropical fish tanks, lowering ammonia can be simple if you follow a few steps. Following these tips and strategies will result in healthier fish and stronger water quality. When you reduce ammonia levels, your tank is less likely to crash and fish deaths are lower than they would be otherwise.