The old wives tell ya to leave your water "sit" for 24 hours to let the Chloramine demons out.

That is actually counter productive.

What leaves the water, is not the Chloramine, but the air.

"Flat" water will drown roots.
Those same roots are happy as clams in aerated water.
They are also quite happy in lightly chlorinated tap water as long as there is enough Oxygen as well.
A few parts of Chlorine per million keeps the micro-herd in check and is no-where near enough to adversely affect Cannabis.

I'll have a few more sometime soon.
Gotta go bum a cup of that coffee from R.T. first.

Aloha,
Weezard