Lighting decisions and live rock choices

[aschke]

Hi all,

I'm somewhat new to this hobby (lifestyle commitment) and I'm setting up my first tank on my own. I've done a ton of research and I think I have most of it all figured out.

I have two questions though. The first one is more important and it concerns itself with lighting. I have a 37gallon AGA tank, which has the same footprint as a 29gallon, 30"x12" but it's 22" high. I think I've decided (resigned myself to) MH with supplemental PCs. My problem, no one makes a 30" hood and I do not want a canopy. I like the look of the Coralife Aqualight Pro hoods and the Current USA Outer Orbit hoods. Is there any reason I can't get a 24" hood and suspend it. It won't cover the length of the tank obviously, but will the lighting still be diffuse enough to provide adequate light to the sides. I want enough light to be able to handle most life in my tank. The other thought I had was the 36" fixture and have it suspended with some overhang (wasted wattage, I know). Is there a third option I'm not considering?

Second, I have not been able to get a straight answer to my question about live rock choices, i.e. live rock origin. Can someone point me to a FAQ or answer this for me?

Thanks
-matt

 

[ChrisRD]

Hi Matt and :welcome:

Lighting choice will vary depending on what you're going to keep in the tank. Without knowing what species you want to keep it's hard to make specific suggestions. That said, we can try to give you some general recommendations...

It's fine to suspend the fixture - many are made to do just that. One thing to think about, however, is that your tank has a centerbrace, right? If so, the center brace will cast a shadow if you use a fixture that has a single halide lamp. A longer fixture might be OK depending on where the actual lamps are (ie. you don't want lots of glare outside the tank).

Personally, for a mixed reef (ie. various coral types with various lighting intensity needs) in that tank, I would probably use two lower wattage lamps (to avoid the shadow issue). Two 150 watt DE pendents would be nice if you're looking for a suspended setup and if you use a bluish-white lamp that has enough output like the 14K Phoenix, you don't necessarily need the supplemental fluorescents.

If two halide lamps is not in the budget, you might consider a fluorescent technology that would penetrate a bit better than PCs, like a T-5 setup with good reflectors.

What was your question about live rock? I don't see another post from you on the board so I'm not sure what question you're referring to...

HTH

 

[ChrisRD]

BTW, it sounds like you've done some research already so I'm not sure how much this will help, but check out the beginner's guide in our library:
http://www.reefs.org/library/newbieguide.htm

 

[Anonymous]

Check out Premium Aquatics for liverock. Their website discusses liverock options very well.

I recently purchase 4 large Marshall Island rocks from them and couldn't be happier with them. The rocks were exactly as described. You can call them and tell them what specifics sizes or shapes you are looking for and they will accomdate you if they can.

I also purchased some Tonga and Fiji rocks locally. It's a good idea to mix a few different types of rocks in your captive reef. It helps increase the biodiversity.

Louey

 

[aschke]

I appreciate the advice from all of you. To clarify about the lighting, I want a setup that will leave me room to grow, without breaking the bank right now. I'm not looking to raise the most difficult corals ever, just some variety.

My tank does have a center brace (or had) but I cut the black one out and fused two strips of clear acrylic in it's place, spaced at 1/3 tank length intervals.

I don't think I can afford 2 MH lamps right now, and I don't like the look of a single pendant anyways. I want some sort of suspended hood. All my problems arise from the seeming lack of 30" long fixtures.

This does raise another question though. I don't quite understand the VHO class of lighting. Are T-5 VHO? What does T-# mean anyway?

And finally, my live rock question. I mean what's the difference in their origin? That is, how is Fiji different from Tonga different from Caribbean and so on.

Thanks again, you don't know how much I appreciate this forum, I've had a ton of questions answered already.

 

[crsswift70]

the t# refers to the number (5 or 12 as ex.)times a fraction of an inch, but i cant remember what that fraction is right now(maybe an 1/8 th)! so, obviously, a t-12 is much wider than a t-5. vho stands for very high output which requires a certain type of ballast but which produces more light for the same size bulb as a NO (normal output). i think the beauty of the t-5 is its small diameter, high light output, and low heat emission.PC's stand for power compact which are usually smaller double tubes. fluorescents dont penetrate water as well as MH so that may also be a consideration depending on the depth of the corals. there is sooo much info on lights that you should probably just read through it all so you get exactly what you need. ive heard people say that MH is the only way to go and others say t-5 or PC's. there are a lot of factors to consider. :wink:

 

[crsswift70]

oh, liverock... thats almost as complex. and by the way, im no expert, im just someone that had to answer all the same questions as you not long ago. the rock from the carribean is usually more dense, thus heavier, than rock from the pacific. i guess more rock for your buck if you get pacific. a lot of the rock from the carribean is also cultured on coastal leases if it comes from florida. so, you may like that idea if youre environmentally inclined. unless you get haitian, they prolly get that right off the beach. i also read that carribean rock doesnt buffer as well as pacific. true or not, i dont know. pacific has a lot more variety in the shapes and densities that come from different regions, ie fiji, tonga and even the location in the water that it comes from out of those regions. i personally just went with fiji "premium". its lumpy and porous with some neat shapes, plenty of corraline, algaes, etc.. i think its the standard stuff. i didnt like the branching because it doesnt fill in as much space. imagine a pile of deer antlers. one again, sooo much to read!

 

[Anonymous]

Hi Matt,
I so understand your delima about lighting. I've upgraded twice now and still not happy with my choices. My tank is a 29 and finding something to fit it was a pain.

I am probably wrong here, but from what I've seem, most hood lighting systems have the ballasts inside the hood, which might make hanging it difficult. And another fyi on hoods, you have to remove them from the tank just to do maint. Some pendants are pretty attractive; such as the aqua medics, very sleek in apperance. Two of those over your tank wouldn't be out of line (that's my next move). You could always get a pc hood that is attractive to you, then retro fit some mh's in.

 

[ChrisRD]

Since it sounds like the center brace shadow won't be an issue, you should be fine with a single halide fixture. If you want some sort of combination halide+fluorescent fixture there are lots of choices out there. Check out our sponsor page - they are quality vendors and many of them carry lighting. A 24" fixture should work just fine on your tank. In the future, if you go to a larger tank, you could just add another fixture/hood of the necessary length (ie. add another 24" fixture to complete the lighting over a 4' tank).

As for the T-# designation with fluorescents, as crsswift70 pointed out, it refers to the diameter of the lamps. The number does refer to 1/8" increments as stated. In other words, a T-5 tube is 5/8" diameter, a T-8 is 1" and a T-12 is 1-1/2". PCs are actually T-5 diameter tubes folded in half. The normal output (NO) fluorescent lamps you're used to seeing in the hardware store are generally T-8 or T-12.

Quick summary of the fluorescent lighting used in the reef hobby:
The three common forms as you probably already know are power compacts (PCs), very high output T-12s (VHOs) and more recently the slim high output lamps (T-5s). T-5s have proven to be the most efficient because excellent reflectors are readily available for them. Because of the thickness/shape of the other two types, they don't lend themselves as well to an efficient reflector design. Fluorescent lamp efficiency is also generally related to lamp diameter, ie. the thinner lamps tend to produce more light and less heat for the amount of power they consume.

HTH

 

[SnowManSnow]

I have a 37g reef with the exact measurements as you have. I run 250w MH AquaLight pendant from AquaMedics. 14k Blueline bulb. It cost $250. I keep anything I want from anemonies to clams in my tank with no problem.

Here's a pic of my tank.

and a pic of how the lighting is set up. the light is suspended from the ceiling and just drops through an open top open back canopy


B.

 

[SnowManSnow]

And here's what I did with my center brace problem.

I cut it out and replaced it with stainless cable left over from my pendant.

There is a post started by Ranger somewhere around here with pics.

B.