I agree that it does sound as you are going through a dinoflagellates outbreak. From the sounds of it, it has progressed quite rapidly and require immediate attention. I would continue to do water changes about 5% per day for about a week. Continue to use the protein skimmer and crank it up. I would also recommend utilizing GFO to contain and eliminate any algae in the tank. I would also crank up the MP 10 and have continued heavy flow in the tank to keep the algae from spreading. Keep softies out of direct flow but good water circulation is needed. I would also check parameters every other day, might be overdoing it but it's better to be safe than sorry. Looking back on your set up, I know from experience that if you keep a bag of carbon and don't clean it regularly, then it tends to do the complete opposite of what it's suppose to do. It becomes a magnet for excess waste to collect and cultivate. Having a reactor to store your carbon is a better choice allowing water flow to continuously tumble over the carbon and replace once a month or as needed. In a smaller tank, utilizing a dual reactor is a good choice with gfo and carbon tumbling around to keep your water crystal clear and free of algae. LMK if you need any additional advice or help. =)