Best timing/tips for full RDWC water change

[Have2]

Hi all!

I was wondering if anyone can chime in about when is the right time to make a full system water change.

I've been able to feed the system with X ppm, damn stable for few days, injecting the exact same ppm of nutrient each day and today, ppm is rising quite rapidly if I don't stop the injection, is it time to do a water change or you follow the "7 days" period? The growth is damn agressive (2nd week of flowering).

Would be nice to gather a list of patterns as to when to do a water change. I would do a chloride and sodium test but the stuff to test for sodium is out of reach $$$

Is it better to do a partial water change after 4-5 days and full system change at 8-9 days? Better to do it each 4-5 days? Going the sterile route.

I'm all ears!

 

[rkymtnman]

why would you want to test for sodium?

and if ppm is rising rapidly, add lots of water until it starts dropping.

there is no "right" answer. some people change every week, some don't for the whole grow.

 

[Have2]

why would you want to test for sodium?

and if ppm is rising rapidly, add lots of water until it starts dropping.

there is no "right" answer. some people change every week, some don't for the whole grow.

Sodium has to be < to 75 ppm...

I was preparing for a water change but my ppm starts to drop again..

I am wondering about water change because each time I do a water change, they start eating like crazy the next day... I am following the good ratio, so must be something that is depleted rapidly... I am leaning toward Ca.

 

[rkymtnman]

Sodium has to be < to 75 ppm

what nutes do you use that you have to worry about sodium content?

 

[Have2]

I am not supposed to have sodium in my water... I use Current cultures nuts but will migrate to my own mix shortly...

About the sodium, it was a point to watch for... Not specific to my situation...

https://cdnmedia.eurofins.com/corporate-eurofins/media/12142795/160825_manual_nutrient_solutions_digital_en.pdf

Even Current cultures has sodium borate in their mix... In their defense, 0.002% so don't have to worry about.

Just trying to chime in in few things people have to watch..

Chloride, sodium...

Which nutes are you using?

 

[rkymtnman]

Which nutes are you using?

i've been mostly a General Hydro guy: flora series, maxi series, floranova series. Dyna Gro Foliage Pro for veg usually. my next run will be with Jacks Tap formula.

but yeah, i just looked at my nute calculator, and there is no sodium in any of the GH flora 3 part line.

 

[Have2]

i've been mostly a General Hydro guy: flora series, maxi series, floranova series. Dyna Gro Foliage Pro for veg usually. my next run will be with Jacks Tap formula.

but yeah, i just looked at my nute calculator, and there is no sodium in any of the GH flora 3 part line.

CS is even using Chloride into their mix...

I took a look into Jack's nutrient too, they seems a good compromise! They even have a RO mix, that is damn great!

 

[DarthVaper84]

Hi all!

I was wondering if anyone can chime in about when is the right time to make a full system water change.

I've been able to feed the system with X ppm, damn stable for few days, injecting the exact same ppm of nutrient each day and today, ppm is rising quite rapidly if I don't stop the injection, is it time to do a water change or you follow the "7 days" period? The growth is damn agressive (2nd week of flowering).

Would be nice to gather a list of patterns as to when to do a water change. I would do a chloride and sodium test but the stuff to test for sodium is out of reach $$$

Is it better to do a partial water change after 4-5 days and full system change at 8-9 days? Better to do it each 4-5 days? Going the sterile route.

I'm all ears!

What is your water source - well or city? And more importantly what sort of pre-treatment (if any) do you do to your water (RO, carbon filtration, etc.) prior to adding it to the reservoir?

If you were to use an RO filter with carbon and sediment filters you’d have no need to test for salt or chlorine, as it would be removed.

 

[Have2]

What is your water source - well or city? And more importantly what sort of pre-treatment (if any) do you do to your water (RO, carbon filtration, etc.) prior to adding it to the reservoir?

If you were to use an RO filter with carbon and sediment filters you’d have no need to test for salt or chlorine, as it would be removed.

I am using RO water, as mentionned previously, nutrients company ARE adding sodium and chloride stuff in their line, not all, but some!

 

[DarthVaper84]

Whoops! I missed that part about RO water.

Since you mentioned calcium in an earlier post, are you adding calcium nutrient prior to the rest of your series? With the GH series Calimagic is to be the first nutrient added to fresh RO.

 

[Have2]

Whoops! I missed that part about RO water.

Since you mentioned calcium in an earlier post, are you adding calcium nutrient prior to the rest of your series? With the GH series Calimagic is to be the first nutrient added to fresh RO.

According to CS, as follow:
UC, coco, veg/bloom a/b, early, mid, late, divorced.
Glad they switch to mid only... No more early, late...