So I’ve had cyano in the past, but never in my pico. Currently treating 50% water changes and chemiclean. Should I do a blackout? No fish, just coral. I have already cleaned both my pumps to maximize water flow. I did a near tear down last weekend, cleaning all the cyano out of the back fudge last weekend, but here I am a week later with the cyano coming back. I plan on doing 50% waterchanges every 3 days while treating with chemiclean. Should I also do the blackout?