Sorry, that sucks. This hobby can be so aggravating when your realize just hoe quickly it can all go south. I say hang in there and don't fret. You figured out and stopped the problem. The worst thing you could do Is stress them out more. I would break the WC in half. Do 15g then see if you think it needs the other 15 the next day or few. The only reason I could see for carbon, wet skimming, and WC would be to remove any slime the corals are giving off under stress.