[sleepswithdafishez]

I have a 20watt CFL 6500k on my 11g fry/Babaulti tank.
Light is about 3'' above water surface ,and at 13'' from substrate.
I also have a glass lid covering the tank.
I've read somewhere on this forum that a glass lid would reduce PAR by not more than 10-15 percent.
Am I in the low light range with this setup?

 

[JJVanier]

Yes I would consider this low light. WPG rule gets fuzzy before 20g and after 90g. CFL if its a spiral, are also inefficient, so you tend to not actually get the 2 WPG you may think you are getting.

 

[sleepswithdafishez]

Yes I would consider this low light. WPG rule gets fuzzy before 20g and after 90g. CFL if its a spiral, are also inefficient, so you tend to not actually get the 2 WPG you may think you are getting.

No ,it is a stick CFL ,but thanx for the spiral CFL tip.

 

[sleepswithdafishez]

This could be of great help to those who may stumble upon this thread - PAR differences between different wattage spiral CFLs ,and their orientation/distance from tank.
http://www.prirodni-akvarium.cz/en/index.php?id=en_squires

 

[goneRogue]

Low to medium is my guess. You can always raise it if it is too much. Alternatively you can use window screen to reduce the intensity.