Well not being a jerk, you knew you had no qt before buying him. The issue is now it will be in the water attaching to whatever is week enough for it to take over. The good news i don't qt either lol. You can do treatments but most will leave your tank no suitable for coral. Natural from what I hear is garlic foods and healthy feeding to keep them fighting it. A cleaner shrimp only eats the small eggs/larva that fall off of im not mistaken. Ive fought if off once and lost one fish to it. Had a powder brown that was in my tank a year no issues, had a cleaning company come in tap the glass and he freaked out, got ich, infested 2 others, he died and the rest fought it off.