Hey Rich, my Cyano got worse originally as well, but then, started to retreat.. I continued siphoning off what I could see on a daily basis until it was gone and did not return. Since I carbon dose, a refugium was not suggested, so I don't run one on my system. However, I do run Ozone on my tank.. I know many don't like to use it, but it will definitely helps to break down the nutrients in your water including the organic stuff that we cant test for.. I thought my ozonizer was running since I set up my tank, but then realized that it was not producing any ozone. Right around the time I started with SB, I replaced my ozonier with and ozotech and conditions improved overall. I mention Ozone becasue of your questions about refugiums, which help to export NO3 and PO4. I ran a fuge on my last tank, did not carbon dose and I never had any isues with cyano and only had a slight cyano outbreak that resolve in a couple of weeks with no action taken by me. However, it always remained in the fuge tangled in my chaeta. I think depending on how our systems are setup and maintained dictate what we need to do in order to achieve simialr results. Ozone is my answer to not having a fuge. So far so good..