Hydro question, some help?

A question from a fellow grower:

I have just set up a grow tent and is ready to start, but this will be my first ever attempt at hydroponics. I have run my set up to work out temps and humidity in the tent.My first question is about water, my tap water is just above 400 ppm and I have to adjust the ph daily as it always changes, I have a rainwater tank and tested the water this morning and its at 9 ppm and ph 7, is it better to use this rain water or stick with tap?? My next question is about flushing, how often should I flush the system?

Starting with water with a very low EC/PPM and with a neutral pH is always best.

I would have to say a starting tap water of 400PPM is way too high, I’d only use tap water if it was below 150 and had a stable pH of no higher than 7.5, and even then I reccomend using distilled or R/O low PPM or zero PPM water if possible, so the rain water certainly would be a much better choice.

Definitely invest in a Reverse-Osmosis unit for your water. Buying distilled is way too expensive and gets old in about 2-3 trips to the store. You can get a decent RO unit for about 80 bucks online.

400 ppm tap water is going to cause you issues when you introduce nutrients to your hydro system.

I also think that if you can drink the water from the rain barrel, and it is ionly 9 ppm (is this correct?) PH 7.0 That would be great water. :slight_smile: