I’ve had brush algae in one of my 46 gallon tank for over 3 years now. It’s one of those algae that are just about impossible to get rid of completely, and it’s recently come back in my 46 gallon tank. It can do well in almost any condition, including ideal conditions. I’ve only found 2 ways to control brush algae:
Siamese Algae Eater
I bought a school of young SAEs to control my first Brush Algae outbreak and they cleaned the tank of all visible BBA within a few weeks. They kept the algae completely out of sight for a long while, but as they got close to full size they started to prefer the other foods I was feeding the other fish. Even though they were eating more prepared foods, they continued to keep the BBA spotty and trimmed. I recently donated the last of my batch back to the LFS and have gained a new appreciation for the job they were doing, as the BBA has come back as strong as ever.
Flourish Excel
Seachem’s Carbon additive is meant to be a fertilizer, so they can’t comment on its uses as an algaecide. They probably also don’t want to comment on how it can also melt certain plants, but there’s no doubt that it can have a significant effect on a tank riddled with BBA.
To use Flourish Excel to control BBA, the idea is to expose the BBA to as high a concentration as possible. The best way to do this is to take whatever the BBA is anchored to out of the water and mist it down with a spray bottle. If that’s not possible, you can use a syringe or pipette to spot treat the BBA in the tank. The 3rd method, which I used in my 46 gallon tank recently, is to overdose the tank. Some people may object to this, but I’m an experimenter, so I have dumped as much as 4 times the recommended dosage into my tanks and have not had problems with it harming my fish or invertebrates. (Think: one-one-thousand-two-one-thousand while pouring…) I can also tell you that it’s amazingly effective, even on horrendous outbreaks. It even works fast. Within 2 days the algae will visibly change color, I’ve seen both blue and red while it was dying, and within a week it will be a dull white color. The downside to this treatment is that the algae isn’t removed from the tank, so it’ll be up to you to reach in there yourself and physically pull each tuft out. Not fun, but I’m doing a little bit each week during my water changes and am almost done. As always with aquariums, a little time once a week is all it takes!
