Should I be concerned?

[Asilavong]

Hi friends!

I'm very new to saltwater aquariums but I've been reading tons and tons and taking it pretty slow. I've had pet water for almost 2+ months now! Haha well my rocks starting to grow what I assume to be diatoms/brown algae (I googled it lol so i could 100% be wrong.) But then, it started looking different. It turned into little round black circles, and now it's almost like a purple color.

Can somebody please be kind enough to tell what is growing and if I should be concerned? I've tried searching the web but I am not confident in my abilities to properly identify what is in my tank.

Thank you!!

 

[andrewey]

Welcome to Reef2Reef!

My first guess is that it is actually cyanobacteria (or more specifically, a combination of cyanobacteria in tandem with various algaes ). If this is the case, you should be able to use a turkey baster to blow some of it off the rock (while some of the algaes should remain). Realistically, it cold be a number of culprits and a microscope is the really only good way to differentiate some of them, but the good news it that in most cases, the solution is time! It looks like the rock is quite new and part of the maturation process of live rock is colonization by different stages of organisms. You can find more information by searching for phrases such as "new tank uglies" or "reef ugly phase". While there are parameters that will help to promote these organisms (e.g. high phosphate), in most cases, time and regular water changes are the mainstay of treatment and you should notice your rock will go through different stages as it "colors up". If I were in your shoes, I wouldn't worry too much about it. Once the tank matures a bit, there are various methods of reducing cyanobacteria, but I wouldn't be opening those doors yet until I've let the rock mature a bit more to see if that's really warranted.

 

[Asilavong]

Thank you so much for your response! I appreciate everything you said and will definitely read up on "new tank uglies" and "reef ugly phase." Thanks again for the advice and direction!