RO water for extract brewing?

[NewEnglander]

I'm in the middle of listening the Double IPA episode and I think I just heard Doc recommend that extract brewers use RO water only for their brews. Am I understanding him correctly that straight RO water with nothing added to build it back up is a good thing if I'm brewing with extract? I have an RO filter for making up water for my reef aquarium and it'd be real easy to put it use for my new favorite hobby as well.

[Bugeater]

It's not really necessary to build up the RO water used in an extract brew. The minerals needed would have already been added to the wort before it was concentrated into an extract. All you need to do is reconstitute it without any additional minerals. As I almost never do extract brews anymore, I am probably not the best person to give advice on this but this is definitely what I would do.

Wayne

[NewEnglander]

So by using RO I'd avoid any questionable stuff in my local water (or the cost of buying bottled water) and just rely on the good stuff the extract folks put in there?
Sounds like a plan!

[captain carrot]

I'm not a water expert (I only play one on homebrew forums). All your minerals are concentrated in the extract. For the IPA you could add some gypsum 1 T and some salt 1/4 t epsom salt and 1/4 t sea salt. This is what I usually add to my all grain IPA's using RO water. For less hoppy beers leave out the gypsum and salt.