There's a few darwin award winners in the hobby and the majority of people are semi lazy. I know only a handful of people that are extremely consistant with their tank maintenance and thats the only way a canister would work on a reef tank without side effects. I don't think people are wrong in saying "OMG! your tanks gonna blow up with a canister filter!!" or other no's to things. The hobby has a pretty flawless set of beginner basic rules and if you follow them anyone can have a successful tank. The people that do run alternate filtration and tank setups are the people who took the time to research and understand very well what they are doing when deviating from the basic rules of reefkeeping.
Canister filters do work with proper cleaning and setup. How well is another story. The main concern is oxygen and trates/P04. Po4 and trates are gonna be higher once you get the filter running. And if your trying to keep your SPS super colorful i wouldn't be running one unless your cleaning it out every 2 days and doing water changes every 4-6 days. Even with the increase in bio filtration from the filter floss its going to pick up ALOT of waste thats gonna sit there for 7 days till you clean it and begin to decay and shove stuff back into the tank. Either way i would say you would need to clean it out alot sooner than every 7 days and shoot for half that.
As far as you making the descision because of a loud skimmer, there are other ways to deal with the noise. Im guessing your sumpless otherwise i would have said just put a filter sock and carbon/po4 reactor and you would have the same effect without having to deal with taking apart a canister filter. Your going to have to unplug the plumbing, carry the canister to the sink, open it, clean the floss, retop it off, close it, carry it back to the tank, replumb it and hope the suction works the first time in the pump. I have a cichlid tank running on an eheim and it's a pain. I'll take a loud skimmer i can just take the top off of and empty it in the toilet over that any day =0)
Also, how are you dealing with salt water loss when your cleaning the floss? And can you post up some detailed info on your tank and inhabitants?
Oh and it will be the demise of your tank if you don't take care of it.
See now this is the type of post I was looking for.
My tank is a 55G. Has a mix of SPS, softies and LPS. I have 2 clowns, a bangaii cardinal, a pink spotted goby and 2 sharknose gobies. I have a vortech 20 and a JBJ chiller. Aquatinics T5s. I tested my water last night before I got rid of the skimmer and Phosphates were 0, Nitrates were close to 0 and Calcium levels were 440-450. Temp is kept at 78 and salinity is 1.026. I dose ESV 2 part and just starte Mg yesterday. I honestly haven't tested the water in a while so I can't provide numbers to back that my tank has improved since adding the fluval in tank. At least I have a good benchmark for where my parameters are before the change.
I don't think having a canister is the sole reason it will be more beneficial. I think having a canister and agitating the rocks to stir up detritus so the canister can filter it out will be what works. I'm not a skimmer expert but I don't think that stirring up the detritus into your water column while running a skimmer actually pulls alot of that detritus out. Yes the skimmer will pull out more because of the agitation, but as far as I know skimmers don't really work that way. However with a canister filter it will at least catch and contain it. By doing that and then cleaning it I am more effectively pulling out the detritus. I spent 3-4 months trying this out with my in tank fluval and i noticed that I pulled out alot more gunk.
Detritus is detritus and if it resides in my canister or in my rocks it doesn't matter. But if I can contain it in my canister, at least I can remove it more easily. My informal test was to stir it up and pull it out. Do it on a weekly basis and there won't be any effective dead spots. It's been working so far.
As for the noise, it is just an added benefit, that wasn't a factor for me removing my skimmer.
I'll try to be vigilant with my water tests on a weekly basis. I tend not to do tests unless something is amiss.