After some time away I finally am getting back to putting my set-up together. I am looking at lighting and it all says to be installed on a tank with a cover. I have a 90g oceanic tech tank. Is a cover just a sheet of glass? acrylic? Is it really necessary? Get one at the LFS? Online?
Thanks - and sorry for such a dumb question.
The SW hobby seems to run through fads on covers. For awhile, all SW tanks were covered, mostly for the same reasons ase FW tanks. Covers keep dirt, pets, and kids out, and keep fish and water in. Then the trend was to use an open top, or no cover. This gave much better gas exchange CO2 out, O2 in. However, the fish could jump out.
I prefer a cover, but others use a screen cover, others use no cover. In a way we are all right.
I use to use glass canopies as the original acryllic ones started to sag after about 6 months. Then I removed them completely and the temp in my tank dropped almost 4 degrees. No need for a chiller. Didnt see much of a difference in evaporation either. The canopies seem to attract salt residue and diminish the light before it reaches my corals. My leathers and colt are fuller and more colorful without the canopies. I will go topless from now on.
It depends on the type of fish as well. Some are jumpers and some are not. I've had trouble with snails and fish traveling into my overflow box but not had one jump (yet!)