Main tank - 90% SPS: Vertex Alpha 200. It's removing a lot of "nasty" stuff. However, I use it predominantly for higher pH (recirc CO2).
Second tank - mixed reef: no skimmer, just chaeto -- no issues. Will remove the chaeto this weekend -- I honestly didn't observe any difference wrt N&P.
It's a nuisance to clean the cleaner cup every week though. If I can get away with no skimmer but still have higher pH, I would. IME, a skimmer is "optional", unless you're chasing higher pH. For example, I'm running with no skimmer, no socks, no water changes, and no problems on my second tank. It's extremely low maintenance - I'm just cleaning the glass every 2 days and takes less than a minute!
Second tank - mixed reef: no skimmer, just chaeto -- no issues. Will remove the chaeto this weekend -- I honestly didn't observe any difference wrt N&P.
It's a nuisance to clean the cleaner cup every week though. If I can get away with no skimmer but still have higher pH, I would. IME, a skimmer is "optional", unless you're chasing higher pH. For example, I'm running with no skimmer, no socks, no water changes, and no problems on my second tank. It's extremely low maintenance - I'm just cleaning the glass every 2 days and takes less than a minute!