PAR readings and glass tops

[CoralJunkie]

Anyone running glass tops and tested their PAR readings?

 

[Chris A.]

They will be lower going through anything specially glass that has condensation on it

 

[ChrisV]

Actually I did this exact test and found almost zero par loss, even with condensation. Maybe 5-10%. Not every glass is the same, so just borrow the club meter to confirm. Ironically, I have another tank with a plexiglass lid that has about 40% par loss.

 

[shrimpchips]

A clean glass top shouldn’t lose too much PAR. Now, who has a clean glass top? Within an hour dust settles down onto it. Within a week it’s visibly dirty. You’re definitely losing light then.

 

[ChrisV]

It may come down to other coatings the glass has on it as well. A clean glass top didn't lose par but a clean plastic top destroyed it.