When you say all out filtration do you mean like overfiltering?
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For example on my 50 display setup I have a refugium with a deep sand bed, protein skimmer, reactors for bio-pellets, Purigen and GFO, a secondary sump with Matrix and pumice blocks for biological filtration and a Magnum 350 canister filter with Seachem's carbon/phosban mix.
the total water volume is probably around 70 gallons
Redundant and some would say overkill, but my stocking and feeding is what most would consider "heavy" and my water parameters now stay on point with very little need for much action or adjustment on my part beyond partial water changes.
I have 7 fish, 4 hermits, 4 nassarius snails, 6-8 astria snails, 2 cleaner shrimp, 1 flame shrimp, 1 camel shrimp, 1 emerald green crab, a chocolate chip star, thousands of mini brittle stars and various coral.
You can run a reef tank with simply live rock and a skimmer, but you have far less margin for error and slight issues could potentially present big problems.