You’ve cycled the water and filled tank. You wait for bacteria to form. You feel good; after all, you did what was needed, or so you think.
Then you glance over to those glass walls, and instead of seeing clear water, you’re seeing a brown, olive-green, dusty looking film covering all surfaces. Slick and resistant to removal, it resembles dust. These is called diatoms or brown algae.
It’s the most typical rite of passage for new aquarium keeper. Frustrating? Yes.
But it also mean your tank is alive. This is where many novice fish keeper lose their cool. They starts scrubbing the glass with a vengeance until their arms fall off.
Within two days the brown slime come back. Now they want to add some nasty chemical. Or change all the water.
Guess what? You’re not battling an invasion of your house with algae. You are actualy battling a natural process of stabilization.
If you’ll learn why it’s there and why it goes away by itself, you’ll save yourself a lot of stress and effort. Diatoms is single celled organism, which is the first point to grasp about them. To create their cellular structure, they use silicates.
Understanding Brown Algae Growth In New Aquariums
What Causes Brown Algae in New Tanks
Most importantly, tap water are usually full of silicates. In addition to your tap water, anything you add to your tank, such as substrate or new decor, brings a nutrient shock to your tank when it’s set up. This shock of nutrients become a buffet for diatoms.
Diatoms only need minimal amounts of light to grow, so they can reproduces quickly. They’re also fast and opportunistic, which means they’ll be the first life form to settle in a new environment. This is where you become your own best friend, patience.
Why the Bloom Is Temporary
The brown algae bloom will be temporary. It simply isn’t sustainable. Soon, what happens is that diatoms grow rapidly, but they don’t dominate either.
Other plant will start taking hold as your tank continues to mature. In order for these other plants to establish themselves, they want more then silicates. They want phosphates.
They want nitrates. Eventually, as the plants establishes themselves, they’ll out-compete the diatoms for those necessary nutrients. They shade the diatoms and essentially remove the chemicals from the water that the diatoms rely on to survive.
Ultimately, the plants is stronger competitors. Fortunately it doesn’t take much on your part to make this happen. Basically what we’re trying to achieve is speed up the natural succession of things happening in your tank.
Tips to Manage Brown Algae Growth
So if you have any live plant, cut them back a bit to force them to grow out again. Not only does this provide more surface area, but it give them more “appetite” for nutrients. Alternatively, you may wish to dim your lights for a week or two as well.
Bright lights will increases diatom reproduction (they don’t require much light). By slowing them down (turning down the lights), you allow your plants time to catch up. Yes, you still need to clean it by hand for looks.
However, alter your approach. Don’t go at it and try to scrub the glass hard. Rather, just use a soft cloth or magnetic algae pad.
Because the algae hasn’t had time to cement itself to the glass yet, it will come off fairly easyly. It’s either another kind of algae you have (in which case I suggest reading up on that) or you’re being too rough. A little light cleaning will keep things in view as the change happen.
Using Livestock to Control Algae
Also consider what lives in your tank. Some small catfish, snails, and even shrimps is voracious algae eaters. For instance, some Neocaridina shrimp consume the brown film all day long.
If you keep them, don’t expect them to completely get rid of the algae. But they’ll keep the algae level low enough that the tank still look clean. It becomes just another element of the tank ecosystem instead of a maintenance task.
Your tank will go through a phase where it’s infested with brown algae but that too will pass as the tank matures. As your plants grow and the bacterial colonies gets established, silicate levels declines. Diatoms starve out.
Typically this occurs in 4-6 weeks after the set-up of your tank. All you’ll see is a thinning out of the brown film. It will be patchy and eventually gone.
There is no magic. It is just ecology at work. Don’t panic when you notice some of that brown dust falling on your brand-new tank.
That’s good…it means something is growing in there. Avoid any temptation to overmedicate or overclean it. Let the system cycle, let the plants grow in.
You should of just wait…the water will get clear…soon.
