common plecos are a no no for me, i lost 3 ornate to a gibby pleco, i read somewhere there are rare plecos that you can make as tankmates that wont bother with your pleco
i have my bichirs with many plecs and thusfar havent had any problems at all. the plecs sometimes chase away the bichir but thats it. i wudnt be too afraid. ive heard stories about plecs sucking on bichirs but i have yet to see the first time...