How many Nbrs I should visit and tour that will increase my social heart rate?

[Fifi0223]

pls someone can tell me
How many Nbrs I should visit and tour that will increase my social heart rate?
How many tour I should make to keep its rate a day?
If I can't play for one week, what can I do before that?
I will told my Nbrs, but can I do more tour before that can keep my heart rate won't go down too fast?
So it the same at pet shop?

Pls & thx

[rionkimchi]

I haven't counted the exact number, but when you reach 4 hearts, the max, then the next day your level drops to 3 with the bar mostly full, and it takes around 20 tours or so (5 photos each tour), to get back to 4 hearts.
I'll try to count it one of these days.

Your level drops the same amount each day, so within a few days you drop to from 4 to 3, to 2, to 1, and then finally to zero hearts. This process probably takes a couple of weeks, because it takes a few days just from 4 (max) until you're at 3 with an empty bar about to drop to 2.