Water question...

G'day folks!
I've been using tap water to water my cacti so far but recently we had a massive downpour and some of my cacti got a drink of rainwater, the effect this had was unbelievable to say the least, in the space of a week they perked up and are looking greener than ever.
My plan now is to switch to rainwater exclusively, the only problem is its not raining and I haven't got any saved.
I know a few people on here only use rainwater so my question is what to water with when there is no rainwater available?

Note: I have an industrial sized container so will be starting to store rainwater in the future but need something in the interim.

Regards,
Walker87

Rain water is better then tap. Tap and rain is way better than bore. I get the same results from tap as I do rain. The trick is to make them struggle through a patch of drought and them give them a big heavy soaking. Soil temps and humidity play big part in how they respond as well.

I use rainwater for cacti through a year, 100%.
Rain fallen over the roof of greenhouse is collected and kept in rainwater tanks.
I calculated necessary tank volume from average rainfall in summer, roof area and possible consumption.

Greenhouse 1. 70 m^2 roof area, 1.6 m^3 tank
                    22 mm rainfall can fill up the tank

Greenhouse 2. 20 m^2 roof area, 0.8 m^3 tank
                    40 mm rainfall can fill up the tank

Grafting cacti are kept in greenhouse 1 and own-rooted asterias are kept in greenhouse 2.
The consumption of greenhouse 1 is larger than that of greenhouse 2.

Water in tanks did never run out even in drought years for last 10 years.
Tanks will be over flow in winter.

I only have access to tap water, however would like to set up a rain water tank. Let us know how you get on walker.

Hellonasty

I am not sure the exact meaning of your question but the movement of rainwater is as follows:

Roof of green house (poly-carbonate roof)
Rainwater gutter (PCV gutter)
Down pipe (90 mm PCV pipe, connecting the gutter and the tank)
Rainwater tank (Steel tank, installed next to greenhouses)
20 mm ID, PCV tube ( leading water from the tank into the greenhouse)
tap (attached a tap at the end of PCV tube, inside of the greenhouse)
Pitcher (received water by a pitcher through the tap and feed water to cacti)

Hanazono