Questions about basing my bugs

I love painting mini's and tyranids are super fun, but I've yet to play a game of warhammer. I understand base size and height of the mini matter in the gameplay and so my question is this: if I build a base for my minis that ends up making them taller does that break etiquette/rules? Pic of my nid prime in my hive fleet colors, and tentacle balloon cause he's cute.