Algae and Nitrate concern

[little_bluecoral]

Hello-

Hoping to get some advice regarding my new nano saltwater tank that is currently in its 4th week of cycling. Believe Diatoms are in my live rock. Any advice or information on these? Read online that this is common in new saltwater tanks but should go away. Another concern of mine is the algae growing on my live rock. Is anyone able to help me identify this? Will be adding more live rock in the coming week. Any information or advice is greatly appreciated for this newbie! 

[billygoat]

Doesn't look like anything out of the ordinary, just some standard diatoms and other filmy algae that are quite common at the start of a tank's life. Your ammonia is gone and your nitrates are high, so I think you might be ready to do a large water change and then add a few snails to start grazing on those rocks. You could also just let the diatoms die back on their own, but you're probably going to want some snails eventually anyway.

 

I can't help but notice that your salinity has been quite low though! Is that by design? Standard for home reefs is 1.024-1.026.

 

Also, be aware that adding new rock could potentially cause a new ammonia spike if it contains a lot of decaying organic matter. It seems from your numbers that your nitrifying bacteria have started to get established, so this should not be a big deal as long as you don't add any livestock until the new ammonia is cycled through. Just something to keep on your radar! 😊