Not to turn this into a wet/dry vs LR & LS debate again - but I love the comment made by Wamp - "It never hurts to overkill yor filtration system on your tank, but it Kills to under filtrate your tank." Maybe that's why i have enuf bio balls for a 180gal on my 75 gal tank - AND just over 1lb per gal of LR.
lol
It 'seems to me' tho... the bacteria grown to consume ammonia and nitrites grow best in a wet/dry than live rock for the simple reason there is 3x the ppm of oxygen in a wet/dry than live rock. Thus to handle an equal bioload - it will take much more surface area of LR and LS to house this bacteria than it will in a wet/dry system. Albeit it a mute point if this vast surface area available is unused.
The primary reason that ppl say wet/dry 'creates' nitrates (which is a major mistatement) is because you have so much filtration that it is said people then "OVERSTOCK" their tank. It is the increased bio load that "creates" the nitrate levels.
GRANTED a DSB will at least help lower the nitrate levels - where nothing in a wet/dry system will.
WHICH LEADS to the introduction of an algae refugium - a great nitrate removal filtration method. This can be done with either a wet/dry OR a DSB. A wet/dry has no nitrate removing ability, thus is a perfect (and most efficient) marrige. HOWEVER, if it does the job of the DSB so well - what is the true NEED for a DSB if you have an Algae-Refugium?
Seems to me - it gets back to 1) personal choice of apperance of your substrate; 2) deciding what architecture of filtration hardware you want to setup (all in 1 tank or multiple specialty tanks); and 3) Do you want to create an algae-refugium or not? Seems the answer to these 3 questions helps steer you to the required setup.
A wet/dry (with an algae refugium) requires more tanks to specialize their function - where a LR & LS method can do it's function in ONE tank. This seems (to me) to be the key difference in deciding what direction you wanna go.
One thing i've learned in this hobby, this is no "BEST" or "RIGHT" way. Good and BAD results can be obtained in any method you use - depending on your maintenance habits; what you put in your tank (types of fish and/or corals); what water source and lighting you use; etc... We ALL do things right AND wrong for our parameters - sometimes whether we KNOW it or not.
I have a friend that has a 180gal tank - has had it for almost 2 yrs now - primarily a Fish Only tank. He bought it established. He LOVES the tank (observer) but to this day STILL doesn't know the difference between Live Rock and a Coral. He doesn't know the process of a cycle. Knowing what i do, which is highly limited, i could point to things he's doing wrong -- using tap water; lighting that is now 2yrs old (never been replaced); no additives whatsoever; infrequent water changes (5-10gal per 2 wks); he has no cleanup crew whatsoever; He doesn't test for ph or anything; etc..
HOWEVER, who am i to say he's a failure because he's not done things right!!?? FACT IS, his tank looks great! lol His fish are doing great. And he loves admiring his tank and the life inside of it. I can't completely explain it - but 2yrs of success speakes for itself.
Now, I don't recommend moving ahead in an expensive hobby blind - but my point - don't focus on the "best", "fastest", "most efficient", "newest", etc way or product. Fact is, the hobby is one huge experiment as we attempt to bring underwater nature into our homes. Learn, enjoy, and do what is best for you - economically, intelligently, what works with the system you have. Learn from others mistakes so that you can succeed. And HAVE FUN - in failures and success.
Best of luck to you, bud.
PS: Wet drys are BETTER than DSB's. My Wet Dry can kick your dads butt any day - it'll kick sand in your face. Wet Dry's RULE!!! DSB's drooool.
Sorry, got carried away.. LOL