Okay, the user wants me to translate "filter-feeders" into Thai. Let me check the rules again. The first rule says to translate all content into Thai. The second rule states that if the content is already in Thai, leave it as is. The third rule is to provide only the translation without any explanations.
First, I need to confirm if "filter-feeders" is in Thai. It's an English term, so it's not. Next, I should translate it. The term "filter-feeders" refers to organisms that feed by filtering particles from water. In Thai, this is commonly translated as "สัตว์ที่กรองอาหาร" which literally means "animals that filter food." I should make sure there's no existing Thai term that's more commonly used. A quick check shows that "สัตว์ที่กรองอาหาร" is the standard translation. No need for explanations, just the translation. So the answer is "สัตว์ที่กรองอาหาร."