cleaner clams

[Montana]

you should be doing at least 10% a week or 20% every 2 weeks especially if if you want to have a clam,or you can add more rock if you currently are not at 1/3 total volume to rock and, carbon will help also but it has to be replaced more often.

[mr_alberta]

Clams use up nitrates in an aquarium. Besides, he's not talking clams like Croceas or Maximas...he's talking grocery store clams that are sold per pound...

[Ruth]

I know that I like to feed my 230 fairly heavily and have battled nitrates a time or 2. I found that adding a lot of cheato to the fuge AND harvesting it regularly helped quite a bit to pull them down. I also went to wet - really wet skimming and made sure to top off with some salt water - helped as well. I used to have large sponges in my sump where the fuge spilled over into the final chamber where the skimmer is. Even though I rinsed and scrubbed the heck out of these sponges on a weekly basis I still found that after I removed them completely my nitrates were noticably lower and through a process of elimination narrowed it down to the sponges. I have since removed all sponges from my tanks with the exception of my 2 Nano tanks as I do not skim these tanks. Filter socks are also notorious for nitrates. HTH
Edit - to the original question in your post I have never tried the cleaner clams but do have various crocea and squamosa clams that have also aided in nitrate buildup.