I would suggest that you rather grow your cells on chamber slides, which are suitable for FISH and fluorescence microscopy such as those from Lab-Tek.

Thank you Sabine. I'm doing special nano scale stimulation performing on stem cells growing on Petri dishes. So I can not change my setup to chamber slides. Any recommendation for this setup?

Could you also grow your cells on slides or coverslips placed in a Petri dish?

In either case, for hypotonic treatment and fixation you have to carefully soak off the medium and slowly add hypotonic solution; after reincubation at 37°C again carefully soak off the hypotonic solution and add fixative (methanol/acetic acid). It might be best to directly add some fixative to the hypotonic solution, replacing it step by step with cold fixative, otherwise your cells might detach from the surface. Fix the cells in the fixative in the Petri dish at -20°C, then remove the fixative and air dry the cells.

Then I would employ a standard FISH protocol; however, I am not familiar with Cambio probes. I would select the area you are interested in and just add the FISH solutions to this area and use coverslips as you would do for a conventional FISH on slides. I think you have to make sure that your Petri dishes have no autofluorescence, may be you have to use a brand suitable for life imaging, may be glass bottom dishes, however, I am not sure whether this will indeed be necessary.

Have you considered using the glass bottom dishes, which can be used for both cell culture and fluorescence imaging, such as this one from Cell E&G? 

http://celleg.com/product/product_7.html