Good day all! New here to the page! Just wanted to get some input on preferences and or reasons to keep your tank covered or opened. Currently I have a 20 gal tall that I have covered. I noticed though that the black strip in the middle creates a little shade down the middle but is pretty unnoticeable. My last tank was a 55 gal with a 20 gal sump. The display was covered but the sump was not and I alway had to add water.. Is there an explanation for why a tank should be uncovered for coral? I know most of my fish would jump out too. Thanks!