New to marine tanks, need some help...

[marvinsae]

Originally Posted by BlueAbyss

A marine tank doesn't have to be 18" thick... I run a 10 gallon planted reef. The live rock goes into the display tank with the sand, the sump is for things like the heater, protein skimmer etc. You want ~10x turnover or lower through the sump (which for a 65 gallon tank, if that's what you decide you want, is around 650 gph or lower). Someone mentioned a filter sock, it goes over the inlet to the sump (where the water from the overflow enters the sump). You can boost your circulation in the display tank with powerheads, as you mentioned... choose something with a nice wide flow, you'll likely want a couple (or more) of them to get some nice turbulent currents flowing around the rock. Skimmers should be rated for TOTAL tank volume, so for a 65 gallon DT and a 40 gallon sump you would want a skimmer rated for 100 gallons or higher.

Now, as far as lighting, don't go by watts per gallon (it's terribly inaccurate). Well, actually I suppose as long as you have more than 4 T5HO bulbs or over a 250W metal halide, you can certainly use watts per gallon, I take that back. It's still going to have more to do with the depth of the water and the lamps you are using, and total distance from the lamps though... what are you planning on keeping? More depends on your plans as to what sort of livestock you will be keeping... are you going for an SPS dominated theme? FOWLR? Different organisms have different needs and the tank should be set-up accordingly.

i wanna have a lot of coral so im guessin an sps dominated theme with plenty of fish also. the guy at my lfs said that mushroom corals and zoanths should be able to grow no problem however i would need MH for other corals and clams?

[Madreefer]

Originally Posted by marvinsae

i wanna have a lot of coral so im guessin an sps dominated theme with plenty of fish also. the guy at my lfs said that mushroom corals and zoanths should be able to grow no problem however i would need MH for other corals and clams?

I would go MH. Imo it's the only way to go if you cant afford led. Only downfall on MH is the heat and power consumption. If you look at most peoples tank thats what they run.

[Fishward]

Originally Posted by marvinsae

i wanna have a lot of coral so im guessin an sps dominated theme with plenty of fish also. the guy at my lfs said that mushroom corals and zoanths should be able to grow no problem however i would need MH for other corals and clams?

Like i said, Fishytime runs 6 bulb T5s and has one of the most amazing tanks i've ever seen. past TOTM also. I have lots of SPS as well and they do just fine under T5s. MH are hot, expensive, and use alot of power, but do give your tank a shimmer you can't get from T5s. (single point light refracts in water better than a line of light) Don't let anyone scare you into buying MH just to keep corals unless you're tank is deeper than about 20-24 inches. past that depth, T5s will not penetrate the water enough and you have to go to MH.

http://www.canreef.com/vbulletin/sho...40669&page=106

[BlueAbyss]

Alright, SPS dominated mixed reef then So you'll need intense light, at least where you're keeping the SPS (clams, photosynthetic gorgonians, some zoas/palys, etc.).

Metal Halide:
1. A great range of lamps to choose from (150W+), most produce more than enough PAR for the highest light organisms (though quality varies).
2. Excellent depth penetration in deep tanks.
3. Natural looking 'glitter lines' because of the single point light source... this is the 'shimmer' that people talk about, and it is undoubtedly the most attractive part of MH. I love it a lot
4. The lamps like to run HOT! Fixtures become uncomfortably warm, and heat is projected which can put delicate corals and fishes at risk. Chillers become common equipment, and they are both expensive to buy and to operate.

T5HO fluorescent:
1. Also a great range of lamps to choose from. Since you are using more than one lamp across the width of the tank, you can mix and match lamps to suit your needs.
2. A 6 lamp unit will grow high light SPS and clams quite well. An 8 lamp unit will grow them on the bottom of the average tank.
3. They are decidely efficient and don't project heat in the manner that metal halide lamps do. Also, electronic ballasts (which further increase efficiency) seem to be the norm.
4. Note that T5 lamps need to have some form of active cooling to maintain PAR (Photosynthetically Available Radiation) values over the lamps' lives. If the lamps get too hot, the phosphor quickly degrades taking some of the PAR with it, though the difference may not be apparent to the human eye.

LEDs:
1. Pretty much the most versatile high intensity light source around. You can build your own array, have one built to your specs, or buy one ready made. Easily dimmable and allows for some pretty spectacular special effects. Lensing (called 'optics') determines light levels and since you need to use more than one LED you mix the colors to get the desired effect.
2. Excellent depth penetration as with MH, and excellent PAR values.
3. The most efficient light source available, and the most environmentally friendly as well. There are LEDs that produce 111 lumens per watt, and though I haven't seen any PAR measurements it's still very encouraging. Also, they don't project heat and they last a VERY long time... Cree XR-Es maintain 70% of their original output after 50 000 hours of use, as long as the junction temperature in the chips has stayed at or below 85C (eg: they are properly mounted and heat sinked or cooled). And still have a serviceable life after that, LEDs don't burn out like regular lamps, they degrade slowly from the second they are put into service (see below).
4. As I mentioned, LEDs output degrades with temperature increase, though not permanently until they hit a certain temperature at which point and beyond they quickly become useless, so heat sinks, fans, and reasonable overall ambient temperatures are required.

For an SPS dominated tank, you'll want at least 50x the display tank's volume as your turnover goal. This includes the return from the sump (the sump should be relatively slower moving, 10x or less), powerheads, wavebox, closed loop, etc. The idea is to have a strong turbulent intermittent flow. Automatic top-off isn't necessary but is really nice. Since it will be SPS dominated, you may consider a calcium reactor or dosing system, and you'll definitely want an oversized skimmer (one rated for maybe 2 or 3x your total system volume) since you intend to keep a number of fishes. You may also consider a zeo or pellet (or other) nutrient reduction system if or when you find your nutrients unmanageable.