Why Is My Aquarium So Dirty?

Keeping your aquarium clean can feel impossible, and there are a few key reasons why you may be seeing algae covering your tank. Let’s get right into it.

Light

Too much light exposure is the most common reason for a dirty aquarium. If your aquarium is getting a lot of natural light, or if you’re keeping your aquarium light on for too long, you’re certainly going to run into the dirty aquarium issue. We like to keep aquariums out of natural light at all times to avoid this problem. The timer on your aquarium light may also be contributing to the algae problem. If your aquarium is in your home, we suggest that you only turn on the aquarium lights when you’re in the same room and enjoying the view of your tank. Otherwise, the fish do NOT need light to survive and you can leave them off for as long as you’d like.

If you want your aquarium lights on longer, we suggest keeping a schedule of 6-8 hours per day. It’s always a good idea to slowly ramp up the light schedule so you can find a happy medium for your aquarium. For reef tanks, we suggest a similar lighting schedule of 7-9 hours per day. A common solution for dirty reef tanks is to lower the white settings on your lights and increase the blue/royal colors. Another trick to keeping algae away is to reduce your red and green settings (if your lights have them) to zero.

Overfeeding

Another extremely common reason why so many aquariums become dirty quickly is due to overfeeding. Fish have very small stomachs and require very little food to survive. Any food that your fish doesn't eat starts to decompose and turn into nutrients that make your tank dirty. It's not only ugly to look at, but it's extremely dangerous to your fish. Making sure you only feed what your fish can consume within a minute or two is crucial for your aquarium's safety. You don't want nutrients like nitrates and phosphates spiking so rapidly, so feeding an appropriate amount can help keep your tank healthy and clean.

Recap

Light exposure and overfeeding are the most common reasons why your aquarium is getting dirty so often after cleaning it. Cleaning your aquarium is unavoidable, and there’s a variety of tools on the market for cleaning algae off of your tank. Before purchasing anything, make sure you know the difference between acrylic and glass cleaning tools.