How to hide total stock?

[prestalearn]

Ive noticed that there is someone who is checking my stock by trying to add as many products as possible, perhaps there is an competitor who tries to get to know my routines...

 

So by adding the maximum amount from time to time he gets to know my stock management.

Is there a possibilty in prestashop that can prevent my visitors to this?

For example I would like to make it impossible to add more than 30 pieces of each item and a popup message that says "please contact us for bigger orders" or something like that...

 

Hope you get the idea what im after, would really appriciate help or advice!