My 1985 3207 draws raw water into the toilet bowls. I meanwhile have two giant freshwater tanks that rarely get used, and nasty harbor water filling my toilet with e coli and everything else that gets washed into our waters these days. Makes sense to use the nice clean freshwater from my holding tanks to flush the bowls.

My toilets appear to be Raritan PH PowerFlush or 1980s equivalent.

I understand the following:
1. There needs to be an "air gap" between the fresh water system and the toilet in order to prevent bacteria from migrating into the fresh water system unless you have a special, commercial product

2. There is a Raritan system for about $220 called "Fresh Head Conversion Kit". NO info on the Raritan site, but it appears to still be a viable product.

Does anyone have experience with the Raritan kit or other home-built solution that fits the requirements of #1?

Thanks, John