Doubt it was Cyano
, with the tank being uncycled. What are your test reading? The carbon really isn't doing much at this time... You can leave it or take it out. I personally would take it out as it will trap some of the organic material that you want to break down and cycle.
32 gallon hex, 34 lbs lr
, Prizm protein skimmer, fluval 104, 1 maxi jet 750, 1 maxi jet 1200 ph
, current 40w 50/50 pc
, 1 NO
powerglo 19watt, 1 daylight NO
65w (equiv), two damsels, 1 green brittlestar, 1 peppermint shrimp, turbo snails, red legged hermit crabs, kenyan tree coral, leather coral, pumping xenia, mushroom coral, green star polyps, orange button polyps