Spawning danios?

• pH:
• Temp:
• KH:
• GH:
• NH4:
• NO2:
• NO3:
• PO4: 0.75
• Iron:
• Dosing: 30 mL (3 ppm iron chelate)

Notes:
I have two zebra danios that I originally bought to cycle the tank when it was new. I had intended to gradually buy a school to finish up the cycling, but I ended up buying a school of harlequin rasboras instead, who stood up to the cycling very well. The two danios were so fun to watch, though, literally swimming through every cubic inch of the tank, that I decided not to return them to the store. I noticed recently that the female zebra danio (very round belly, less yellow than the slender male) seemed agitated, taking gulps from the surface every so often. I immediately checked the CO2 levels, which were okay. The female has been hiding a lot as well, except for when the male chases her around. I wonder if they are planning on spawning...