Seriously need glass cover on tank for T5?
 

Reading the manual for the Nova Extreme Pro (6 T5's) it says must use a glass or acrylic cover on top of the tank even though it has the splash guard. DO you adhere to this policy? I've always just used eggcrates on my tank since glass captures heat. I am almost going to go without the eggcrate on this new one since I have no fish jumpers now!

Just a precaution or a serious risk?

its just a precaution. almost nobody in the saltwater hobby uses the glass tops.

don't use a glass top. using a glass top doesn't allow or breathing in your tank which keeps everything too contained. Algae and junk you will never be able to get off the top will cover it before a years time and just **** you off as to why you even bought it because it will become a huge filter and your light won't penetrate as it needs too which defies the point of the T5's.

Thanks.
While we're at it, does the eggcrate I use diffuse much light?

what is the dimensions of your egg crate ... the larger the egg crate, the less light is diffused, but if its more narrow, like mesh, than yes, it does diffuse the light ... in terms of telling how much, you'll need a par output kit to tell that

I find that the egg crate works pretty well. It is designed to dispurse light a bit without blocking too much of it. It hardly seems to make much of a difference with T5 since they ae already pretty well diffused just from the bulb design.