Topping off res question

Usually people change it every week to 2 weeks. Some wait longer. It all depends how u want to do it.

I usually change the rez every week so i dont need to top it up. But yes you can fresh water, just check ur ph and ppm after.

it is so much easier wwith 5gal dwc to just mix a new batch every week in a new bucket and just swap the top and pkant over. and you dont have to worry about elements building up. also, you didnt say what stage you are in but 6.0 is the top of ph for the last three weeks of flower. a little lower is better before that.

Well my plant has probally drank half of the res, so I can't wait. I'd rather do a complete res change every 9 or 10 days instead of once a week.... Also on day 6 of 12/12 flower and I try to put the ph in the low 5 range so when it creeps up it goes to 6 range.

the roots act like a wick. it is no problem for the res to go down. let them eat the full meal and then serve them another.

Anyone else ???