Originally Posted by kungfukoi
The refugium has it's light on 24/7 and the macro algea (calupra, and one that looks like green thread.)
The macro algae sounds more like chaetomorpha which is not a gaulerpa species. Can you post a pic?
So my question is, as the Title suggests... Is it necessarly BAD to have Cyanobacteria in your refugium?
The presence of cyano
is usually from a few issues but one in particularly inherent to refugiums on occasion. The slower flow makes it much easier for this type of nuisance to get hold. If this is a newer addition to the tank, it could simpley be "growing pains" and may yet subside on it's own. The main culprit in it's cause though will primarily be from PO4
. I would suggest checking on those levels as the first step. Nitrates in themselves will not usually start the problem but are a great fuel source for maintaining the cyano
's growth. A few water changes with RO
water should help with the NO3
. I would also reduce the lighting back down from 24/7 and opt for a reverse lit setup. This will allow for much stabler ph
at the same time limiting another possible fuel source being the light itself. Personally, I have found if the spectrum of the bulb being used is too yellow, it will also spur on unwanted algae growths. If possible I would look into a "bluer" spectrum bulb or possibley an actinic 03