Orangish stuff on tank rocks

[bunger2]

Help! I started a 20 gallon tank a few months ago -- just a community setup, ~76 degrees F. No problems, water is nice and clean, pH is relatively stable.. Recently I noticed a moderate carpet of red growing stuff on the rocks at the bottom and on a few items in the tank.

I think it might be algae, but I don't recall ever seeing red/orange before. Could this be harmful, and do I need to get rid of it?


Thanks,

Ben

 

[Shaunna]

Is this a saltwater or freshwater tank? What are it's inhabitants?

 

[bunger2]

Freshwater. I've got a couple of zebrafish, a dalmation fish and a tetra (also had a pleco until this morning )

 

[Shaunna]

Does it look like this:http://www.plantgeek.net/articles/gg_algae_faq/brown2_curt.jpg If so, they are diatoms and usually indicate an excess of bad stuff in the water that needs to be reomved by a water change or they can also be from a lack of light. They are easy to get rid of by wiping the glass and vacuuming your gravel. They will also show up pretty heavily on a recently cycled tank. The fact that you lost a pleco kinda makes me curious as to when your last water change was and how much?