Lighting levels?

[jrp1588]

Well over the weekend I got a little bored and decided to try to educate myself in lighting beyond the WPG rule. After a fair amount of digging and learning about different methods to measure the lighting level of a tank, I became extremly confused.

I have a 216watt Catalina Aquarium t5 kit with individual reflectors over a standard 75 gallon. Using the WPG rule factoring in the increased efficiency of t5 vs t12, I obviously have high light...But then I began looking into lumens/sq in. Several websites put my tank in several different light levels. One even rated my light at medium-low and another at very high. I understand how to go about the math, but I'm confused why their scales differ so widely.

I seriously gave myself a headache doing this trying to find some consistency when I should have been doing some reading. Anyway, where would you put me?

 

[SpeedEuphoria]

You have "Good Light" IMO. Meaning enough to grow pretty much anything with CO2. Without CO2 you prob have too much light even for excel.

Some of this depends on how high above the tank the fixture is, or you can adjust your lighting level by raising/lowering the fixture height off the tank.

 

[jrp1588]

Don't worry, CO2 is next on my shopping list. And my fixture is basically right on top of my class canopy. There's about a half inch gap.

 

[Purrbox]

Unfortunately lighting is more of an art than a science. There are just too many variables to accurately say how much light any one fixture will provide, especially since so most bulbs only list power consumption (watts) and not light output (lumens, etc). The best way would be to use a light meter, but they are too expensive for most of us. This is why you were getting such varying answers when looking at your lighting.

You definately have enough light that CO2 will be required to avoid algae. After that it will be trial and error to see what you can grow. I'd guess you'll be able to grow most anything that you want except for possibly some of the highest light loving plants.

 

[jrp1588]

well that's good enough for me I suppose.