55 gallon lighting

[Jacca]

I am building a hood for my wife's 55 gallon tank. I am going to use 23w cfl bulbs. The plants she has are wisteria, banana plant, and an Anubis (not sure the kind). How many bulbs should I put on the hood? I have a 10 gallon running 2 of these bulbs now and it is an algae farm.

 

[KittyKat]

How deep is the tank?

[From my experience…]

Assuming the light output from these is the same as from T5 and T8 fluorescent tubes per watt (both of those are almost the same), then aiming at 1.5 wpg will allow her to grow almost all plants she can think of.

So, if she wants no hassle, then 3 bulbs; if she is planning to experiment with plants, want red plants or the tank is 2 ft deep, then 4 bulbs.

p.s. 4.6 wpg that you have on the 10 gal is manageable… but you'd need a lot of floating plants! I recommend you try water lettuce, that stuff is nice and would love the higher light

 

[Jacca]

The lights will be about 20 inches from the substrate. The bulbs are 23 watt 6500k screw CFL bulbs (equivalent to 100watt incandescent bulbs)

 

[KittyKat]

So, wikipedia says..
Compact fluorescent lamp - Wikipedia, the free encyclopedia : the CFL outputs around 70 lm per watt
Fluorescent-lamp formats - Wikipedia, the free encyclopedia : the HO T5s and T8s output around 90 lm per watt

Given the difference between the two, I would estimate that fluorescent tubes produce 30% more light per watt, so to aim at 1.5 wpg T5/T8 equivalent, you would need around 1.9 wpg.

Through how many inches of water? If all 20 are water, then I'd edge towards 5 bulbs, but if only 16-18 are water, then towards 4. Keep in mind that different people work best with different lights! I've grown anubias well under both of the lighting amounts with success and prefer lighting to be on the higher side of things.

Having done a quick search on the interwebs, I can see that banana plants apparently like the medium to slightly less amount of light.

p.s. your actual 4.6 wpg on the 10 gallon is closer to 3.6 wpg of T5/T8s that some people use for measuring lighting nowadays, but others still use the T12 tube output when they talk about wpg

 

[Aspencer]

There is a light chart that is floating around here and on my home computer...it compares depth and bulbs, one or two...and what level of light your receive. I will post it when I get home if no one else does it.