Id only maybe suggest it is a bit short for the danio's as when they get to their max size of about 2 inch they can be quite boistrous?sp.
Other than that id say your pretty much ok there, its key to just keeping the water changes correct, which at 30% a week Id say are sufficient.
As long as you don't overfeed to the point of polluting the water, i always beleive "stocking" rules are kinda rubbish, they are just there for the basic help for beginners imo.
Good morning and welcome to the forum! +1 on the zebra danios. They really do need the room to zip across the tank. I never really gave that much thought until I moved mine into a 4ft tank. They are much happier now. I'd say as long as your water parameters are good and stable and you keep up with your weekly maintenance, you should not have problems with your stocking.