After removing previous sealant with Stanley knife, do you recommend wiping the area with specific cleaner to prepare the surface for new sealant? Do you recommend letting the area dry out for period of time before applying new sealant? If so, how long? Do you recommend certain types of sealant? Do you recommend clear or white sealant?
Providing it's clean is all that matters. Make sure you've removed all the old sealant. A blade from a Stanley knife will shave off any remnants.
I suggest you let it dry out fully after cleaning with a regular bathroom cleanser. 12 to 24 hours should do.
I'd recommend you use a silicone sealant of the best quality. Don't skimp on a few pennies or you'll only end up doing the job again in a year's time.
Colour is a matter of personal aesthetic.
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