lighting

[SHIFT_Unique]

ok i have a 55 gallon tank.

do i need a 48" light, because all the 48" fixtures have 2 bulbs in a straight light

example: [------------------][-------------------]

my current power compact fixture on my 29g is a dual set-up

example: [-----------------]
[------------------]

i like it that way so i can mix 10-12k bulbs with actinic bulbs equally, instead of a actinic being on one side and a 10k being on one side, have a split colored tank.

the tank will be full of plants, but no C02

[kaz]

a t12 has 2 long 48 bulbs like your second sample not like the first.

[SHIFT_Unique]

but will it provide ample wattage. 130+

[dapellegrini]

Are you planning on using PC lights? Either way you described will work fine. In example one, you would use 2x 50/50 PC lights, in example 2 you would use 1 of each. However, if you are going for a low-light, planted tank, using Actinic bulbs is not particularly recommended (some claim it makes algae an even bigger problem).

Regardless, when you count your useful watts of light for your plants, do not count any actinics that you are running. For instance, if you are running 1x 12k and 1x Actinic Blue, both 65watt PC bulbs, you have 65watts over your tank that your plants can use. Same if each bulb was a 50/50.

Plants aside, any level and type of light is fine for your fish.

[SHIFT_Unique]

its more for my plants and looks. i have a freshwater setup, no inverts

what kelvin of light will give me a cool blue light. thats full spectrum

[dapellegrini]

There are no full-spectrum equivalents to effect/look of Actinic Blues. 10k or 12k lights are about as close as you can get.

[SHIFT_Unique]

how much watts is not enough for a 55 gallon

[dapellegrini]

Depends on the type of light and the plants you will keep. Even avoiding CO2, you will probably need to dose fertilizers for your plants.

Anything over 2 WPG and you are treading on thin ice, IME. I think others have pushed it farther. That is assuming your standard T-12 lights. PC, T-8, T-5, and VHO lights are much more efficient per watt, and you would need less of them.

I haven't had incredible success with low-light setups but if you post the question in the Planted Forum, I am sure a you will get a lot better response there.