Every fish enthusiast likes having a beautiful, clean and presentable aquarium to decorate their home with and proudly show off to their friends and family. Maintaining a tank, however, takes dedication, time, effort, and a good amount of knowledge on how to take care of the inside environment.
One of the most annoying and unpleasant occurrences are dead spots.
You can tell your aquarium has dead spots, if you notice small, dark circles appearing on the walls of the aquarium or debris piling up in areas where the water movement is missing.
In cases when the intensity of the water movement in the tank is decreased, nooks and crannies can also become dead zones, collecting food remnants, unwanted algae, and dirt.
Make sure you keep the water circulation in the tank at good levels at all times to avoid such unpleasant occurrences.
What Are Aquarium Dead Spots?
Aquarium dead spots are small piles of dirt, debris, waste, etc., occurring when the water movement in the tank is insufficient or the filter is not strong enough to clean the water well.
Usually, they are small brown formations on the walls of the aquarium, the pebbles on the bottom or at the holes, nooks, and crannies where your fish like to hide. In most cases, they should be obvious and easily noticeable.
Food, fish waste, and algae gradually begin to pile thus causing uncleanliness and eventually begin to decay.
It is important to keep an eye on your aquarium and take measures immediately after noticing dead spots. If the dirt remains in the tank for too long it can be poisonous for its inhabitants and even deadly for the aquatic animals inside.

Are All Brown Spots Dead Spots?
No, not all brown spots are necessarily dead spots, especially when you first set up your aquarium.
If you are just starting out, you might notice brown spots forming on the sides of the tank. Brown algae are a natural occurrence when setting up a new fish tank as the system needs time to mature. It takes between 4 and 6 weeks to achieve a healthy balance within the tank’s system and to establish its bacteria and nitrogen cycle.
Nevertheless, remember that this is a natural occurrence only when you are at the very beginning of setting up a tank. Such spots appearing later should be a sign of that something in the system is not working right.
How Do I Get Rid of Dead Spots in My Aquarium?
There are several measures you can take to fight dead spots. Let’s take a closer look:
1. Increase the water movement – as mentioned, dead spots are most likely to occur when there isn’t enough water circulation in the tank. Make sure the powerhead of the filter is strong enough for the size of your tank. If it’s not, purchase an additional powerhead or install a bigger filter.
2. Add more plants – plants have the ability to absorb unwanted algae and food remnants.
3. Keep up the maintenance – make sure your tank is cleaned regularly and the water is filtered properly.
4. Feed your fauna less – give your fish the exact amount of food they need and no more. Providing more food than necessary may lead to the fish not eating it, thus remnants get stuck in stones, holes, pebbles, and the tank’s walls.
5. Maintain proper aquarium lighting – sufficient light access helps keep the healthy balance of the aquarium’s environment and substances inside thus preventing algae from forming.
Is a Fish Tank Supposed to Have Bubbles on the Glass?
A well-maintained tank is supposed to have bubbles on the glass and this is normal.
When you are first beginning to set up a new aquarium, agitation is created causing bubbles, and even a slight foam on the surface. Filtration and aeration can also create bubbles that are completely normal.
In fact, bubbles are a sign of good aeration of the aquarium. They show that the aquatic inhabitants get enough oxygen. Since pumps are usually installed close to the glass, it’s normal that bubbles to appear on the glass.
Air bubbles can also appear during water change or when adding new water to the existing one.
How Do I Increase Circulation in My Aquarium?
Good water circulation is important for your aquarium – it keeps the tank clean and fresh, preventing dead spots and algae from forming.
You can increase the circulation by adding a powerhead. Position it to pump water from the back of the tank so the water hits the front glass. Thus the water flow from the filter will be complemented helping to keep the aquarium clean.
Can Fish Live in Dead Zones?
Dead zones in water are areas with low–oxygen conditions also known as hypoxia.
Since the oxygen levels are below normal for plants and fish to survive, fish cannot live in such zones for a long time and the environment forces them to move away.”
To sum up, from dead spots in aquariums to dead zones with no oxygen, fish or any aquatic animals cannot last for too long in dirty and toxic environments. Old food, fish waste, and unwanted algae eventually start to decay-causing poisonous waters that can be fatal to your aquatic pets.
Keep your tank clean by ensuring enough water circulation, oxygen supply, and regular water change.
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