algae question

Question
hello...i have a 100 gallon freshwater tank with exotic angelfish, a few tetras for movement, lots of plants, driftwood, siamese algae eaters, etc.

i have two large powerhead on either side of the tank with an underground filter plus a large canister filter.  the ammonia, nitrates,  phosphates are 0, the ph is 6.8.

i do a 20% weekly water change using soft water...the angels require this...my tank is spotless except for these brown "tufts" of brown algae growing on filter parts, plants, driftwood, side of the tank....the only way to remove it is to scrap it off!

i have tried many algae removal products...the latest...the highly touted ALGONE...for six week, with little positive results...i am very frustrated..can you help?...thank you, regards, john weber  

Answer
Hi John!
It sounds like you have a beautiful aquarium and care very much about your fish!
You Are taking great care of your fish but I notice you didn't mention how long the lights are on in the aquarium... As you probably know already, nearly every type of algae needs two things to grow and flourish--- light, and nutrients. I don't suspect your nutrients are a problem in that large a tank and not having large, dirty fish either. So this leads me to believe excess light could be your problem... A typical planted tank should recieve about 12 hours of daylight each day, Anymore than that and you may get algae trouble. Make sure this isn't the problem. If this doesn't seem to help try doing more frequent water changes to remove any possible excess nutrients, just to be sure this isn't the culprit either.

The algae you have could be fuzz algae...It is often considered normal for planted aquariums and usually grows on  plant leaves. It should be easily controlled by algae eaters though. Then again, it may just simply be brown algae which is actually diatoms. The presence of Diatoms indicate a LACK of light! And usually increased light levels make it dissapear. But this algae is more easily removed by simply wiping and you mentioned you had to scrub it off. Please try natural methods for algae control. Chemicals are hard on everything and almost 98% of the time, algae can get gotten rid of by means of light and nutrient control. You could also try adding more plants or a species whom is known for being an excellent competetion for algae. Water sprite is excellent. Ancharis grows fast and is a well-known oxygenator. But your problem may also simply be an excess of light.

Remember in a lot of planted aquariums, you will almost always have some algae growing. Keeping planted aquariums healthy also allows a healthy enviroment for algae to grow in some amount. But most of the time you can easily get rid of it by carefully controlling the amount of light, nutrients, and having good algae eaters such as your Siamese.

I really hope this helps! I'm sorry I would have replied much sooner but I've been extremely busy! sorry...

Let me know how it goes if you don't mind!
BEST of luck..

Happy fishkeeping!
Karen~