I would never tell anyone to avoid surface skimming.
That's bad advice.
Let us be practical for a moment.
Light= better light use with SS
Films, less with SS
Better filtration, hides tubing with SS
Why not? Supposedly some claim it removes CO2. If you raise the level inside the over flow, then it does not remove much to ever be an issue, anyways, why is it an issue?
I can easily add a tad more CO2.
If you are sat the limit of CO2 addition, then you have something wrong with the CO2 system(inefficient/not enough flow through/ undersized for the tank etc) not the surface skimmer.
The other safety thing is that the levels of O2 will not drop as much with SS and Wet'drys etc if something goes sour with plant growth or with low plant biomass.
I can bring any plant back that's taken a beating, I cannot bring fish back to life.
Just for clarification:
The HOB skimmers we are talking about are not protein skimmers, they are overflow box surface layer skimmers.
CPR and various other brands are all good, the less amount inside the tank, the better.
I always add a piece of 1/2 cork bark etc to my skimmer boxes to hide the things, then add plants like Java fern etc to the cork using U shaped wire nails/staples.
You cannot even tell what the overflow is after I get done with it.
As far as heavier particulate materials, a large weekly water change removes all that.
You will lose a little CO2, but it's not anything to fret over, it's easy to add more CO2 and cost very little.
I had a 90 gallon tank with DIY CO2 yeast, and a wet dry(unsealed) and used 4 x 2liter bottles changed every other week without issue with very high lighting.
So it can be done effectively even with weak CO2 sources.
But it's much wiser to have a CO2 gas tank system with larger than 40-50 gallon tanks.
You might lose 5-10% CO2 at most, but given the cost of CO2, using it 10 hours a day, and 5-10% loss factor relative to cost, say 15$ for 10lbs of gas, that means you will spend about 1.50$ more per year or to 6months so in added CO2 gas cost.
Oh my wallet hurts
If you gassed your fish or have lower DO levels or loss light levels will add up to more $$ faster I'd suggest.