screen lid affect lighting?

I decided to cover the top of my tank with a screen. I want to get a fire goby and don't want him to be able to jump out. Will this significantly affect the amount of light transmitted to my tank?

 

No

 

With all due respect to packleader...

absolutely it will.

Window screen blocks about 40-50% of the light through it.

Egg crate blocks about 10%, not as noticeable, but it has an effect.

Most window screen will have printed on it the amount of light it blocks. You can buy more expensive screen that claims to block less light, but I doubt it's much.

 

I agree with greysoul light is blocked whenever anything is placed between the light and the bottom of the tank. Look at water for instance, clear as can be but par fluctuates greatly from out of water to just in the water and reduces the lower you go. Acrylic shields do also and they are clear.

 

Anything can block light but I really dont think a screen is going to be the difference between a coral growing or not growing so if you want to be safe go ahead with the screen.

 

if you use screen, just dont run it underneath the lights. can be cut to fit and attach it with velcro .

 

I do know acrylic cut the PAR value down some but I have never used or researched a screen....but assume anything but air will cut the PAR down somewhat..I doubt it would be 50% percent though if that were the case then two layers would be total darkness...haha...
Danny

 

I have added egg crate to my tank. It has much bigger holes than screen.


My coral hasn't seemed to mind, but the tank is noticeably darker to me (but only to me, my family doesn't notice).

 

assuming 50% reduction in visible light... two layers would be a reduction of 75%.

50% reduction in layer one and then layer two would reduce by 50% the half that gets through layer one (which would be 25% overall). So 50+25 = 75%. It would never, theoretically, block 100%. Just half of half of half of half of half, infinitum.

 

Hmmm, good discussion on this point. I didn't want to use egg crate because the holes are too big. A fire goby could jump through them. I also didn't want to use acrylic with holes drilled because I'd always have to clean the salt creep off of it. I can't cut the screen around the lights because the lights are suspended above the tank...So I guess I have no choice but to accept a bit of light reduction.