just had mine 1st spawn last week. you should leave the eggs in there but once the fry start to swim take them out. I made the mistake of leaving them in the tank and a days or two after they started to swim the parents ate them.
hopefully second spawn will be coming soon.
I don't have a established tank set up. I do have a penguin 200 and a ac50 on my 20 gallon tank. Can I just go out and buy a new 20 gallon tank and put that filter on it with some water from my original 20 gallon and be good and not to worry about cycling?