What is this growing?

cyano is not on its own harmful to fish. Do you have a good clean up crew? If not, having a varied crew will help for sure. I would suggest that smaller weekly changes would be better so you can siphon it out.

 

My only cleanup crew is 2 small fire shrimp and a starfish. I'm looking to get some snails and crabs in the future.

 

I would suggest getting one sooner than later, that will help a lot - less direct intervention on your part needed

 

Thank you for your help everyone. I talked to a few people at my LFS and they suggested leaving the lights off for a few days and then doing a large water change, siphoning the cyano off the rocks. Being that I don't have corals to worry about I will try this out.

 

i had cyano outbreak about year n a half after setup, i was guilty of overfeeding.

btw, awesome tank birthdate! i was born on dec 27 too! :2thumbsup

 

I'm sure that will help Justin but you really do need to get a clean up crew

 

Reefcleaners.org is a good place to get a CuC. my tank is a little older than yours and I had an awful outbreak of cyano. i bought a CuC from that website and they went to town on the cyano and are still keeping it in check. The crews they sell that are snails only are what I would recommend to you.

 

+1^^

reef cleaners is great. very helpful, way less expensive than at an lfs. he does customized packages on request too