Why is my ec increasing???

Can somebody please explain to me why when i put in a fresh mix, into my ebb and flood resevoirs, at a concentration of exactly 2.5, why is it that 5days later the nutrient concentration has risen to 3.8??? will this cause overfertilisation of the plants?? i have noticed the leaves on a couple are yellowing...whats causing this increase and how can i stop it?? Also the same with ph, its increasing out of the acceptable range within a week....i use all canna products which are supposed to regulate the ph themselves apparantly, but this doesnt seem to be happening at all!

Driving me mad...

I would guess evaperation is causeing this. When water evaps it leaves the nutes behind, thus becoming more concentrated.

Have you been topping off your reservoir?

I don't grow in/know much about hydro, so I'm just throwing out guesses here.

Na i havent been topping it off, i usually just wait till the water is all gone then just do a fresh mix....

What should i top it off with, just ph'd water??

switch said:

Na i havent been topping it off, i usually just wait till the water is all gone then just do a fresh mix....

What should i top it off with, just ph'd water??

Click to expand...

Again, I'm no hydro-guy, but I believe I've heard people saying they top off their reservoir. As the guy above me said, your reservoir is evaporating and leaving nutrients in the water are staying in the solution.

And I would say yes, just ph'd water.

switch said:

Na i havent been topping it off, i usually just wait till the water is all gone then just do a fresh mix....

What should i top it off with, just ph'd water??

Click to expand...

yes just water

sweet, thanks guys, yea that does make sense to be honest

If your plants use more water than nutes the EC will go up, if they use more nutes than water your EC will go down.
Top off your res. with PH adjusted water only, and you will be straight.

fresh water only - adding more nutes to a nute mix can be a waste of time even lock out some nutes.

My guess is that evaporation is causing this, as previously stated when the water evaporates it leaves behind the nutes increasing concentration of the solution, in turn increasing youre EC.

What you should be doing is, if you had a 10 gallon res, topped with youre required amount of nutes, keep topping the tank up untill you have added HALF the orriginal amount, in this instance it would be 5 gallons. Add the required amount of water needed to top off, then check youre PH accordingly everytime you add and balance. Once you have added half the orriginal amount, it is time to empty the res, fill up with fresh water and start again... This is the best method. I also use canna products and it works well for me. Hope this helps.

Im a hydro guy. I top my tank and add nutes to the number I want it to be at usually 1000 to 1200 ppm for veg. In flower its higher and being I run 24 buckets on each system the ladies drink quite a bit. I get lots of evap and drinking so have to keep up on the ole deal.

Also bear in mind that obviously you want to be checking and topping up idealy on a daily basis, and if you find you only top up say 2 gallons and youre EC is below the required level after this, youre plants are using lots of nutrients, more than the amount of water, and it is time to empty up and refill with a fresh nutrient solution. Idealy you would want to change this after a max of 5 days anyway...

Nice 1 guys!