Things You'll Need
Salt water (for rinsing)
Bowl or plastic container
Oil slicks in an aquarium can occur from a number of different sources. The most common reason is overfeeding. Marine foods high in fat will build up over time and float to the surface, causing a slick to form. Other reasons may include waste from your live animals, particles of oil in the air from your kitchen, or even the death of an animal in your tank. Whatever the reason, with a few household items and a little time, this is a pretty easy problem to tackle.
Removing an oil slick
Identify the source of the problem. Check your fish food and see if it has a high fat content. If this is the culprit, then simply cutting back on the amount of food you put in your tank will resolve this issue. Feed your fish only what they can eat in a period of two to three minutes. Do not let food lay on the bottom of your aquarium. As the food breaks down, the fat is released into the tank and floats to the surface, causing the slick.
If the food is not the problem, then you will have to check your aquarium for dead animals, or even the air flow around the tank. Once you have identified the problem and have dealt with it, you are now ready to remove the slick from your tank.
Unplug your filter and pump. While removing the oil slick, you want the water in your aquarium to be still. This will allow the oil to collect at the surface of the tank for easy removal. Let the tank stand still for about 10 minutes. After this phase, take a paper towel and lay it across the top of your tank. This will absorb the oil slick. Make sure not to let the oil from the paper towel drip back into the tank.
After most of the oil slick has been "mopped" up by the paper towel, take your sponge and clean the sides of the tank. This will remove any oil that is clinging to the front or sides of your aquarium.
Remove all of your filters and media from your aquarium. Rinse them off using salt water. Make sure all of your items are oil-free. Once your filters and media are clean, you can place them back into your aquarium.
You can also use a chemical like Pro Clear to help remove oil from your tank. This chemical will clump oil, food and loose debris in your tank and allow you to remove them with a net. Most local fish stores carry Pro Clear. Following these easy steps and proactively eliminating the causes of the problem will ensure that you have a healthy, oil-free aquarium.
Identify what is causing the oil slick. Oil Slicks are easy to tackle.
Lack of surface agitation can cause slicks to build up on the surface of your tank. Do not rinse filters or aquarium media in your faucet.
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