Fertilize a mango tree in bloom?

[Herman]

Hello mango experts!

I was wondering whether or not to fertilize a mango tree that is flowering, and if so, what fertilizers should be used?
Is there any time that the tree should NOT be fertilized during bloom?
Also, I've heard that, for the first year a mango ever flowers, it should not be allowed to fruit so that the fruit would be better the following year.  Does it really make a difference?

Thanks!

Herman