I'm so worried about my rainbow shark. I've had it for a few months now, and it has done very well until now. I'm thinking it could be ick or cotton mouth. There's a white, salt like substance around its nose/mouth area, it's fins are turning white around the edges, and it's just not acting normal. Not eating and hanging out around the heater instead of hiding from me. It was fine this morning, and I did a water 10% water change today. Thanks in advance for any help!