Although you know for sure that you added clear water inside your aquarium, for some reason, over time it gets green at first, then darker and darker in color. It might get to the point that the water is so foggy green, that you can barely see a fish or two. This is something aquarium owners will have to deal with a lot, and there are a few ways in which you can fix it.
The article below will not only make you understand why the fish tank water is green but also what you will have to do to make it crystal clear again.
What turns aquarium water green
To make sure you’re taking the necessary steps toward solving this issue, you must first understand what is behind the water inside your aquarium turning green. The simplest explanation behind green aquarium water is tiny parts of algae that multiply endlessly. These are actually living things, but they are so small that you can only see them with the help of a microscope. They are called phytoplankton. The phytoplankton will multiply to the point that it gets very concentrated in your tank. This will make the water turn green and it is actually called an algae bloom. This is something you will have to take care of, to prevent the water in your aquarium from turning thick and yellow-green.
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The first thing you need to understand is that this type of green water won’t harm your aquarium plants or fish. In the wild, they will also have to deal with phytoplankton. Even so, this is surely not something you want to see in your aquarium.
Too much phytoplankton can be caused by one of three issues:
Excessive light
Considering that phytoplankton is a type of algae and algae is a type of plant, like most plants, it will strive under enough light. The green bits might multiply excessively if leave the light on for too many hours each day or if you have an aquarium light stronger than the tank would need.
An aquarium exposed too much to sunlight can also get green fast. Algae really like natural light, so even if the tank light is off, if you keep it too close to a window, it will get overexposed to light, which would increase the levels of phytoplankton inside the water.
Out-of-balance nutrients
A properly made aquarium will have aquatic plants and these plants need a certain balance of nutrients to develop. The bad part is that algae will also enjoy those particular nutrients. Algae strive in harsher environments so an imbalance of nutrients inside the tank will make aquatic plants lose their glow, while algae will strive.
Not enough tank maintenance
If you want an aquarium with clear, beautiful water and you also want to prevent it from getting green and cloudy, then you will have to have it maintained periodically. The life in the tank will require some basic maintenance to stay healthy, like water quality testing, filter cleaning, and water changes. A lack of periodic, proper maintenance will usually contribute to an overgrowth of algae.
Fixing your green-water problem
The first step in fixing a green water issue is to find out what is behind it. There are also instances when not one, but multiple factors will contribute to the problem, which means that the solution will also be more complex.
Use a UV sterilizer
An ultraviolet (or UV) sterilizer will help you if you want a simple and very efficient solution to getting rid of the green water right on the spot. It will usually take a maximum of a few days for the water to get clearer because the UV chamber will eliminate algae as soon as water flows through it.
Although the UV sterilizer can help fix your issue, green water might be caused by something else and you should make sure you fix the root of the problem as well. Before considering getting a UV sterilizer, you should first go through the steps below to make sure you spot what’s wrong.
Reduce light
If you believe that the excess algae growth is influenced by too much light, then you should start by reducing the amount of light hitting the tank. Go for a lower-wattage bulb and don’t keep the light working for more than 10 hours each day. Also, if you keep the tank close to a window, they try to move it slightly so it doesn’t receive as much natural light and check it periodically to see if anything changes.
Fix water imbalances
The levels of the chemicals inside the tank are also important, so make sure you have them checked. While testing the water, you might notice that the levels of phosphate and nitrate are imbalanced, which can be considered a reason for algae growth. Your nitrate and phosphate levels will usually get higher if you have more fish in the tank than you should. To solve this water imbalance you can do one of these two things: Either put the fish in a larger tank or reduce the number of fish in your old one.
Adding more plants should also help. This is because Plants will usually eat the same nutrients that algae need. As long as you have a decent amount of plants, usually, algae won’t have enough nutrients to grow.
Clean your tank
Even after finding the root of the problem and going through the steps above, you should never neglect regular cleaning and maintenance if you want to avoid algae and green water. It is very important to change at least 20% of the amount of water in your tank once per week. This is so important, that you should set a calendar reminder, to make sure you don’t miss this chore.
