DSB or not? lighting good enough?

[i-CONICA]

hi, i'm just starting out again after a four year break from reefkeeping, i have set up the tank and got most of the equipment.
i am using coral sand and i have between 3.5 to 5 inch depth of it through out the tank. will this be deep enough for a dsb?

aditionally, i know what type of filtration i want but im not sure how to implement it.
i like the sound of the filtration system where you just have live rock and a skimmer with lots of power heads along with a good skimmer.
i dont have live rock at the minute im just using ocean rock(was live years ago(its cheaper) ) i presume bacteria will colonise on this? i have four strong powerheads with sweeping action heads on them to simulate waves with a decent skimmer and i have just bought a 250w halide unit with two 39w t5 actinics and led moon light. does this sound good? do i really need live rock for this filtration system to work? and can i mix live rock and ocean rock to save money? will that lighting unit be good enough to keep corals in the future? the tank is a juwel rekord 120L lots of questions, hope you can help, thanks.

[AQTCJAK]

Sounds like a good start to me

[wonderloss]

The benefit of live rock comes not only from providing a substrate for bacteria to colonize, but also from the diversity of organisms that it brings into the tank. The variety of worms, zooplankton, etc. all serve a role in the aquarium, such as scavenging detritus or being a tasty meal for the larger inhabitants. I would definitely advise adding some amount of live rock to your ocean rock for this reason.

[framerguy]

SAND BED:Typically DSB's are 6"+ deep. This takes up a lot of viewing space in the aquarium so most people who employ DSB have them in the refugium. Although I think yours is so close it will function fairly well. Just make sure your rock is placed on the tank bottom or supported in some way, maybe with eggcrate to prevent burrowing animals to cause a cave in of rocks.
FILTRATION:A closed loop system is very popular way to provide water motion and to get water to your mechanical filtration system. It uses a sump and return lines. Your refugium with DSB could be incorprated in the sump as well. However, To just have power heads in the tank and no closed loop you would probably use a hang on skimmer, the Aqua Remora C is very good. You would be relying heavily on your live rock for filtration so use your ocean rock as base rock and get some good quality Live Rock to seed it. There's nothing wrong IMO with that approach.
LIGHTING:If I calculated correctly (I probably didn't) a 120L aquarium is 31~ gallons so the light you have is around 9.5w/gal which is excellent for light loving corals and anemones. And maybe to much for some.
DISCLAIMER: While I'm no rookie, there are dozens of people more knowlegable than me on the excellent site. If anything I have told you is incorrect they will let you (and me) know.

[Melanie]

My very UNscientific observation is that DSBs look "dirty" in all the photographs I have seen. Layers of yuck that you can easily see in pictures.

[BigAl07]

I like the benefits of DSB but like Melanie noted they just tend to look "dirty". I'm running a SSB of 2"-3" in my display tank and in my refugium have a DSB.

Allen

[blue_eyes53813]

Hello Welcome to RS.. Your set up sounds great..