compact flourescent question

[ohio reefer]

as you might know i'm in the process if setting up my 120 gal (48x24x24). I'm going to use 2x 250 watt MH (6,500k or 10,000k can't decide).

i saw that hellolights has their 2x 55 watt ARO CF ballast kit- square pin. on sale $69.99. or do you think i should go with 96 watt.

will this be enough light? what is the difference between these and power compacts?

i want to keep everything sps, clams, etc.

please let me know what you would do with your 120gal!

TIA

mark

 

[fishfreek]

CF and PC are the same.

96W bulbs are 3' long where as 55W bulbs are 2' long. Having a pair of 55W bulbs would give you greater coverage and just slightly more light. I take it your wanting to have the PC's be actinic?

If you doubt the 2 X 55W setup then maybe you want to think about doubling that.

 

[ohio reefer]

would this be adaquate for a full reef set-up? or do you think 4x 55watt be better?

thanks fishfreek

mark

 

[ohio reefer]

also isn't the general rule of thumb 2-3 watts per gallon?

mark

 

[Guest]

The watts per gallon rule doesn't apply when dealing with MH lights. With a 120, 2X250's will be good but you are going to want at least a 4X55 watt PC 03 Actinic supplement... Now of course you could go with the 20,000K MH bulbs and have prolly a good blue hue....

 

[brndfrb]

watts per gallon doesn't apply when dealing with mh?

 

[TheMadNucleus]

Hi Mark,

You have some very good questions and I think the answers depend on a lot of variables. It also depends on how concerned your are with the health of your inhabitants as well as the appearance of your aquarium. Sometimes these two items are at odds based on what you are keeping. In fact many aquariums largely contain species from a variety of areas each with varying natural environments and different demands for lighting. (not to mention water chemistry).

It is a rough job to try to find a happy medium between all of these constraints. I would not even venture a guess as there is a lot to making these decisions. However, I would like to suggest that you take a look at some of Bob Fenner's comments on Marine Aquarium lighting and its objectives:

http://www.wetwebmedia.com/marine/setup/lighting/index.htm

I personally think that we are all a little too light crazy. In fact , based on the output of many of these hi-intensity MH 20,000k bulbs we are effectively having home fish fries.

Well, hope you take a look at that particular article (link above) it is really comprehensive and will perhaps give you enough info to answer some of these questions. Particularly note that Depth is more critical than watts/gallon.

Lata'

Tom

 

[fishfreek]

No it doesnt. THe reason is lets say you put 1MH bulb in the smack middle of a 4' long tank. Sure its 250W and sure thats just over 2W per gal but the bulb is not going to be lighting up the entire tank evently. There will be a bright spot in the middle and the sides will be heavily shaded. So the center will get the most light and the sides will get almost none.

This is why we always suggest 1MH bulb for every 2' of tank lenght.

Florecent bulbs will light up the entire length of the bulb and the light is evenly distrabuted over that lenght so if you have a bulb lets say 4' long you will have basicliy the same intensity thru the entire lenght of the bulb. This is why 2 2' bulbs end to end is better than 1 3' bulb because you get greater coverage.

 

[reefrunner69]

The truth about lighting


Corals, light, pigments and junk

Two very interesting threads on another forum which kind of go hand in hand with the discussion.

 

[ohio reefer]

i appreciate all the help.

but would i be able to keep a reef with 2x 55 watt CF and 2x 250watt MH?

the money is kinda of tight and i only was able to get the above

TIA

mark

 

[reefrunner69]

but would i be able to keep a reef with 2x 55 watt CF and 2x 250watt MH?

Yes, you should not be too limited in the animals you want to keep either. Towards the sides and front (on the bottom) of the tank you might find some sps and clams difficult, but towards the center even on the bottom you should be fine.