fruit fly treatment question

[mcf57]

I am about to change out a toilet. While I have the old toilet removed, can I pour some fruit fly drain treatment down the toilet line? Or should I still pour it down a nearby sink (like I have done in the past)?

Also, I have always used a regular wax ring when installing new toilets, but I now see these plastic toilet flange kits that claim to be better. Are they better or should I just keep using a standard wax ring?

 

[breplum]

I haven't seen surveys, my colleagues and I typically carry a variety of WC seal options depending on situation. With flange is usually first choice, given well placed closet flange. many permutations: Extra deep, adding single wax , other varieties have come and gone, always new ideas.