The Brown Phase
So you’ve just set up a beautiful aquarium, but a few weeks later it’s covered in brown stuff! What went wrong?!
Nothing! On the contrary, this is actually great news! This brown algae is formed by diatoms and different bacterias. The term “brown phase” has been coined by reefers to describe this phenomenon. If you think you can skip this ugly phase, think again. No matter your set-up or intuitive methods, the brown phase is ultimately inevitable.
Because everything inside a reef tank is living (yes, even the rocks), there tends to be an equilibrium. Due to all bacteria and lifeforms starting at ground zero, cyanobacteria, diatoms, dinoflagellates, and algae take over quickly thanks to limited competition. Hence, the brown phase.
While many want to dump in chemicals and bleach their rocks to clear the diatoms, this can do more harm than good. Most of these bacterias are self-limiting and clear up on their own, while simultaneously feeding good lifeforms. The key to leaving the brown phase once and for all? Patience. It’s actually the key to most everything else in reefing too, so this is a great time to start.
Diatoms
New salt, new rock, and new water are all capable of producing silicon, and when you add all of these at once there’s a high chance you’ve got a lot of it. These diatoms bond together in brown clusters and typically form on your sand, rock, and glass. It usually takes two to four weeks for diatoms to form, and about four months for them to dissipate.
Silicon is the eighth most common element, but is rarely seen in its actual form. This is why you may have heard of silicon dioxide (silica) or silicates, but not silicon. Silicon is commonly used in construction or found on natural materials, such as your aquarium’s rock and sand.
A great way to combat diatoms is to introduce copepods and inverts to your aquarium. These will also be beneficial throughout your aquarium’s lifetime.
The brown phase is not just limited to diatoms. There’s a few key variations of bacteria during the brown phase, so let's go over each one.
Cyanobacteria
Cyanobacteria is unique because it is photosynthetic and can pop up in even the most established tanks. When detritus (brown sludge generally made up of diatoms) breaks away and falls into a dead spot, this becomes a breeding spot for cyano. Seemingly clean, cured rock can also attract cyano due to unforeseen living bacteria that was killed off during the curing process. Cyano is not destructive unless it begins to cover coral, so it’s best to take care of it during the beginning stages. Cyano can be spotted due to its unique red and purple coloring.
The first step to combating cyano is to wipe out as much of it and any nutrients it can feed on. Doing a water change while siphoning as much cyano and detritus as you can is a great start.
To prevent it from coming back, make sure your tank is getting equal amounts of flow without any dead spots. You can find these dead spots by looking at where the cyano is thriving.
If the cyano continues to come back with a vengeance, Chemiclean does a great job of eliminating it. You can find it at any local fish store. Just follow the instructions, and they’ll have you back on track in no time.
Dinoflagellates
While dinoflagellates are not typically as common as cyano or diatoms, it’s much more stubborn and destructive. Dinoflagellates are single-celled organisms that are a kind of gray area due to them having characteristics of both plants and animals.
Dino starts due to an imbalance of nutrients and is extremely stubborn. Because it’s so hard to get rid of, it can take over quickly and start suffocating coral and any beneficial bacteria. Dino is always present in aquariums, typically in the form of cysts in fish’s guts or the base of aquaculture. However, copepods and beneficial bacteria should be the dominating bacteria and subsequently beat out dino.
Balancing your nutrients and running a UV sterilizer are the main go-to ways to eliminate dinoflagellates in your aquarium.
We hope this blog helps you understand the brown phase and leave worry free! Have a suggestion for another blog? Let us know!