Hi HelpingNemo and
to TR.
I don't have a nano-cube type tank so I can't answer questions specific to them. But anytime something looks muddy it sounds like it needs cleaned! I am sure that there is biological filtration going on in the sponges and ceramic media so you can't just pull it all out at once and clean it or you will have a massive nutrient spike. How much
live rock do you have? What corals do you have? Are you using tap water to do water changes and top-offs? (Just in case you don't know you replace evaporated water with fresh water.) How long are you burning the lights?Bristleworms are good detrivores and won't hurt anything. However, an over-abundance of them means there is lots of food available for them so you may need to cut back on how much you are feeding.
