Are there any algae's that are bad in a reef tank?

I have a yellow algae developing on the walls of my tank which I normally clean. I also have some brown and green coralline algae developing on the rocks. Are any of these algae's bad and what colors of algae should I be cleaning up? I also wanted to add that my tank had been up and running for only 3 weeks. Also, I only have 3 small fish in a 30 gallon tank and have been doing water changes every 2 or 3 days. Thanks

 

Any algae that you can rub and it comes off easily is not coralline and you wont want. Some algaes like cyano can choke the bacteria in your rocks or sand if they get a think enough layer down.

 

I heard when your starting your tank, brown and green algae are common? Also, does most of the 'bad' algae accumulate on the glass of the tank or on the rock as well where the coralline algae is? Thanks

 

They are very common at the beginning because during the cycle ammonia nitrite and nitrates are high which they feed off of. Most algae will live just about anywhere.

 

Yes,both brown and green aigae are common in new tanks.At three weeks you should be seeing a lot of diatoms,brown dustlike algae,its not harmful and wiil soon go away on its own,just clean it from the glass if yould like.However, by doing water changes at this point your probably slowing down the natural "cycle" of your tank,just let it go for a couple months.You need to test for ammonia,nitrites,and nitrates as well as ph,if you dont have these test kits you should definitely get some soon.When your ammania and nitrites are reading zero your nitrates should begin to rise.Its at this point that a partial wter change would be good.Hope this helps you out and best of luck with your new tank,Dave

 

All the info you should need right at your finger tips:

http://www.3reef.com/forums/algae/ultimate-nuisance-algae-thread-58657.html

 

Yeah. That's the thread I was looking for the other day when someone was asking "what is this pink cottony-looking stuff in my tank."
Thanks, greysoul.

 

long live the well organized sub forums with sticky topics!