Once you get it set up, look to start at about 1 to 1.5 bubbles per second. This should give plenty CO2. Also remember that if a tank get's pretty thick, in other words, heavily planted, I would run an airstone at night, or a powerhead directed at the surface, to cause aggitation. Plants produce O2 during the day, but use O2 at night, and could strip the O2 from the water, killing your fish. I had this happen when I was very heavily planted. But now I run powerheads that ripple the waters surface, and have not had that problem.
As for running it during the day, you can. But remember, more surface aggitation requires more CO2 to be added, or a higher bubble rate. You don't need any surface aggitation during the day, but I recommend it after lights out.
Lastly, BBA is caused by a fluctuating CO2 level. If your levels are too low, and keep dropping out, you will get BBA in due time. Also, have a ph and kh test kit to keep tab on your CO2 levels until you get your bubble count to the desired level. Your goal is a minimum of 30ppm, up to about 50ppm. This will give the best plant growth, IMO. I generally keep mine at a minimum if 45-60ppm, but I'm probably running a ton more light than you will be, as well as have a much more densly planted tank. But the minimum should never go below 30ppm. Some say 25ppm, but I like being a little more than bare minimum. lol.
And remember, feel free to ask any questions. We are here to help where we can.