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Vinnie71975
11/01/2007, 01:53 AM
Ok i was wondering how many watts total you would recommend for a 20g long tank? i want to be able to keep Zoa's,Leathers, and Mushrooms. Would 2x65watt PC be ok? No mh please too much heat and cant afford to run them lol

tinysuperbug
11/01/2007, 02:12 AM
For just zoas leathers and softies, that should be plenty.

Another option would be one of the 24" 2x t5 nova's . Bulbs should last almost twice as long. Should be enough for a softie setup.

http://www.drsfostersmith.com/Product/Prod_Display.cfm?pcatid=16770&Ntt=nova&Ntk=All&Ntx=mode+matchallpartial&Np=1&N=2004&Nty=1

Vinnie71975
11/01/2007, 11:12 PM
<a href=showthread.php?s=&postid=11094451#post11094451 target=_blank>Originally posted</a> by tinysuperbug
For just zoas leathers and softies, that should be plenty.

Another option would be one of the 24" 2x t5 nova's . Bulbs should last almost twice as long. Should be enough for a softie setup.

http://www.drsfostersmith.com/Product/Prod_Display.cfm?pcatid=16770&Ntt=nova&Ntk=All&Ntx=mode+matchallpartial&Np=1&N=2004&Nty=1

ya but would 48 watts be enough light? Or the 78 watts the 78 watt set up is only 3.9 watts per gallon which i know isn't a catch all but the fixture a was looking at is 6.5 watts PC Per Gallon and is 30 inch with mounting legs which is what my tank is and the prices are very close to the same. i just want to be sure i have enough light in the tank

lastduke
11/02/2007, 12:26 AM
Also LPS okay? I have the same qeustion about the light density

coast2coast7390
11/02/2007, 12:59 AM
zoos
shrooms
anenomes
LPS
softies
all should be fine in 4 watts and higher

lastduke
11/02/2007, 01:14 PM
so that 48W T5 fixture can not meet the 4 Watts per gallon . T5 will have better lighting density than PC, do we have to keep 4 Watts per gallon rule for soft and LPS?

coast2coast7390
11/02/2007, 01:19 PM
<a href=showthread.php?s=&postid=11103459#post11103459 target=_blank>Originally posted</a> by lastduke
so that 48W T5 fixture can not meet the 4 Watts per gallon . T5 will have better lighting density than PC, do we have to keep 4 Watts per gallon rule for soft and LPS?

its a good base line for softies and LPS...

kau_cinta_ku
11/02/2007, 01:22 PM
the only reason the nova unit isn't prob good enough is because it uses only 1 reflector for all the bulbs. if it was a T5HO unit with a reflector for each bulb it would beat the PC's hands down.

lastduke
11/02/2007, 01:28 PM
what about this , price is not high. Is this good enough for soft and LPS? http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+3733+13822+15491&pcatid=15491

kau_cinta_ku
11/02/2007, 01:43 PM
even though those have individual reflectors they won't help out much due to the design of the reflectors. if your going for T5's, reflectors are everything. here are some good ones and don't cost much more.

http://www.reefgeek.com/lighting/T5_Fluorescent/IceCap/SLR_Retrofit_Kits/

http://www.reefgeek.com/lighting/T5_Fluorescent/Sunlight_Supply/Tek_2_Retrofit_Kits/

tinysuperbug
11/02/2007, 05:16 PM
Watts per gallon is pretty much a useless comparison with all of the different lighting technology that is out there.

I can take a t5 with the same amount of wattage and get way more output with good reflectors using the same wattage.

The thing about the 20Long is the fact that it is quite shallow. In my experience if you go with the individual high quality reflectors on a 2x t5 setup you would definitely be able to keep lps and probably some sps as well.(in a 20L). t5's penetrate very well, even better than halides, which can be a problem for lower light corals if you have a shallow tank . Depending on how you mount it you can adjust the height off the tank to adjust intensity though.

Those nova retro's aren't going to be tons better than the nova 2x, although they will give you more output. Definitely enough for softies (lps too and maybe even some low light sps) though in my opinion.

lastduke
11/03/2007, 01:53 AM
You mean CURRENT¡¡24" 2x t5 nova is good enough for 20L soft and LPS setup?
If it is correct, I am going to buy this light.
I am sure, If i can keep this 24 reef, I will invest bigger tank and better light. so I dont' want to spend too much on this small tank and lighting system.

tinysuperbug
11/03/2007, 02:24 AM
The Nova 24" 2xT5 should be enough for softies and maybe some lps, in a shallow tank like the 20L. it has a reflector/bulb setup like this:

____
/ o o \

The Nova 24" t5 Retro will give you a bit more light due to the fact that it has individual reflectors like so:

__ __
/ o \ / o \

This reflects the light that is lost between the lamps down into the tank. This should be enough for softies and lps and perhaps even some lower light sps such as monti caps (on the higher points of the aquascape)

The most light you can get from a 2x t5 setup is one using high quality parabolic reflectors such as the one posted earlier on reefgeek.

These reflect all light back into the tank due to reflectors designed something like this:


_ _
/ V \
| O |

Now onto the disclaimer. I have not personally used either of the novas mentioned above, but I do have experience with a 20L and High output T5's. A 4 bulb t5 using this reflector configuration:
__ __
/ o \ / o \


is actually too much light for even lps in a 20L

So I believe the regular 2x nova should be fine if you are only looking to start with softies such as mushrooms and such. The problem with the shallow 20L is that if you go overboard on the t5's you can actually have too much light for mushrooms, and other low light softies, and some lower light lps.

Hope that helps.

*EDIT* Not sure why, but rc is removing some spaces from my diagram so the tops are not lining up with the rest of the reflector diagram.

lastduke
11/03/2007, 02:48 AM
It does help, thanks a lot. Know more about T5 difference. I am going to go with option 2 , buy from local used or web new lighting