Lighting Question

[slipknottin]

reference to what?

When we use watts/gallon we are referring to fluorescent type lighting. Otherwise my 90 gallon tank would have around 50 watts/gallon of lighting, and my 10 gallon tank has something like 90 watts/gallon.

Watts/gallon is a horrible rule of thumb anyways, 28 watts of CF lighting is only going to be around 2100 lumens. Not that bright at all.

from thekrib.com
conventional incandescent: 500PAR64, 6500 (initial) lumens, 500 watts,
13 lumens/watt
halogen: 50PAR30 (GE Halogen IR), 1000 lumens, 50 watts,
20 lumens/watt
fluorescent T12, GE Chroma 50, 1870 lumens, 40 watts,
46.75 lumens/watt (on a ballast that only draws 40 watts, heigh ho)
fluorescent T12, GE rare earth, 2960 lumens, 40 watts,
74 lumens/watt (but this depends on the ballast)
fluorescent T8, GE rare earth, electronic ballast (!), 2650 lumens, 27 watts,
98 lumens/watt
fluorescent compact F40/30BX/IS, electronic ballast, 2840 lumens, 30 watts,
95 lumens/watt

 

[bizzy928]

Okay, lets just scrap the whole watts per gallon thing.

10 Gallon Tank
2x14w CF that output 800 Lumens Each (1600 Total)
The colour temp of each bulb is 2700k

1) Will that be too bright for my fish in terms of lumens?
2) Will that be sufficient lighting/nutrients for one aquatic plant with no CO2?

My concern was that with the existing incadescent bulbs rated at 25w and lets say 600*2 lumens, if I exchanged the 25w with a 14w CF that outputs 800*2 lumens, that extra 400 lumens is going to be to bright for my fish and their eyes.

 

[ChilDawg]

The answer: it depends. Nothing is too bright for fish if they are provided with sufficient floating greenery to diffuse and even block out light altogether.

 

[bizzy928]

Originally posted by ChilDawg
The answer: it depends. Nothing is too bright for fish if they are provided with sufficient floating greenery to diffuse and even block out light altogether.

Could you name some examples of "floating greenery?"
Meaning it does not have to be planted?

Are these plants hardy? And would 2*2700k CF suffice for their survival without CO2?

 

[ChilDawg]

I'm thinking about duckweed in particular, but I don't have a good grasp on what it would need for lighting/CO2 requirements. Hopefully someone else could answer that!

 

[slipknottin]

If your refering to the floating greener when you ask of C02 then its a mute issue. Floating plants can take C02 direct from the air.

As for the bulbs, if you can, I suggest you find bulbs with a higher K value. A bulb of 2700K will be predominatly in the red and yellow spectrum. Plants benefit from a spike in both the yellow and blue spectrum, which is why bulbs of around 5500K are most common and most recommended.