Securing wash basin & toilet into floor

[bettz1]

Hi we've just had out bathroom floors tiled in porcelain tiles.

I'm about to put the toilet back on and the washbasin,tilers mentioned that I'd get away without having to drill the toilet down and washbasin and that silicone will hold it secure?

I plan to secure the sink to the wall as it's not porcelain and would save me buying a diamond drill bit or would it be worth doing

 

[B17NNS]

Ideally you'd use a mechanical fixing but with a bit of Dow 785 it won't move.