lighting question

[Xenia123]

I bought a Coralife Aqualight PC fixture with lamp and the instruction said "this fixture is for use over covered aquariums only" so I went to home depot to buy the glass and cut it to fit the top of my tank and put the light on top of it. I am just wondering why the tank top must be covered. Is it a safety issue or the light will operate more properly to deliver the beneficial light with the glass cover?

[chuckdee]

It pretty much is a safety issue. If you don't cover your tank, you might come across some salt creep or splashing water, and it could possibly cause they light to malfunction..

[lunatik_69]

Do the pc lights have a cover? or can you actually touch the bulbs? I dont see the need to cover the tank, just install the legs or hang them at least 6" from the waters surface.

[sssnake]

Originally Posted by lunatik_69

..I dont see the need to cover the tank, just install the legs or hang them at least 6" from the waters surface.

Totally agree. Much better to have some open space on top for heat escape and general aeration of the water surface.

[reef_guru]

the glass will lower the light efficiency with the exception of de mh where a sheild is needed. there should be a sheild on the light fixture already. the top of the tank should be open for air exchange. so lunatiks suggestion is right on the money.

[Xenia123]

This is from the manufacturer :"Place the Aqualight fixture on top of clear aquarium cover so that the lamps provide maximum exposure of beneficial light to all inhabitants and plants." I was thinking the same as reef guru said the glass will decrease the light efficiency. I didnt cover the top completely there is space in the front and back of the tank top so i think aeration wont create much problem. The cons is it might decrease the efficiency of the light and aeration. The pros is I like the way it look with the glass on top and also might prevent objects from falling into the tank accidentally!
I am thinking to add Duro Test's Vita Lite full spectrum light to make up for the decrease light.They are cheap and can run on a rugular fixture. I heard they are good?

[Otty]

You never want to cover the top of a sw tank. That is where you get your gas exchange. Warning labels are on equipment to save the company's butt in case of a law suit.