If you really just want to sit back and let the tank do the work, get peppermint shrimps. It sounds like you probably have a large enough tank to hold a good amount, and they apparently love to eat the
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. I truly am concerned, I just come a bit harsh when I dont feel like I am being taken seriously. Pepermints, I think would be a better choice than the nudibranchs, as they tend to just disappear, and take a while longer to make a difference. Good luck and let us know what happens.