What happens when I never change the rez? Also PH not drifting quick enough?

Indoor Growing
#1

I am lazy to change the rez because I need to bring water myself to the grow and also it is a pain to drain the rez…

I forgot when I changed the rez last time… Two months? Or three??? Idk… :smiley: I put in every two days 100ml h2o2. Rez temp stays under 25. No slime! I have always around 100 to 200 liters in the rez. Every couple of days I add 60liters osmotic water and add general hydroponics lucas formula (no extra calmag).

The micro(or milli?)siemens seems to be always around 1,9 to 2,2.

When I need to add new water the ph never is higher than 5.9. After adding new water and nutrients the ph goes down automatically to 5.7… I bring it up with “ph up” to at least 5.8…

My plants are now maybe 3 weeks in flower. Lower leaves get yellow… So I am wondering if maybe it has to do with old rez contents…

@ReikoX said that if my Ph never goes up to 6.2. I will get deficiencies… Probably that is the reason?
Yesterday I upped the ph to 6.15…

Hopefully that will help.

But I am wondering how can I make my ph drift up to 6.2??? My plants conusme the water so quick and ph raises slowly…

Also are there any issues that I get when I not change the rez?

4 Likes
#2

There’s a couple scenarios.

Bacteria could start to take over, and if you seed your res with the right beneficials they may keep it in order for you. Might make res changes unnecessary for relatively long periods of time.
You could also keep it sterilized, and then same thing, nothing to worry about for a long while.

As the plants take up what they want tho, the NPK in the res will slowly change based on what they leave behind. This could be why you’re seeing yellowing.

Of course it may also just be the plant naturally dropping leaves that aren’t pulling their own weight.

5 Likes
#3

The problem with not changing the res, is you have no idea what is still left nutrient wise. So, for example, if you plant isnt updating nitrogen, it will start to build up. Granted, I have only done hydro a handful of times. I usually top off with plain tap water every week and refill the resivoir every other.

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#4

I run dwc and top off with ph water and change res every week to 10 days. My ph starts at 5.76 and i letit drift up. If the res is at say 5.9 I’ll ph the water to that so it can continue its swing

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#5

How do I reach 6.2 ph? My ph doesn’t swing that fast. When I add my nutrients and new water, the ph gets lower and lower actually…

How do I know if a leaf isn’t pulling its own weight or if it has something to do with nutrients?

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#6

Baking soda will help raise the ph.

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#7

Don’t use baking soda… That has sodium in it. Use a pH Up designed for horticulture. Better yet, use potassium silicate, because then the plants get silica supplementation. I use Pro-Tekt by Dyna-Gro.

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#8

Copy and pasted from another site
Sodium is not an essential element for plants but can be used in small quantities, similar to micronutrients, to aid in metabolism and synthesis of chlorophyll. In some plants, it can be used as a partial replacement for potassium and aids in the opening and closing of stomates, which helps regulate internal water balance. Chloride is needed in small quantities and aids in plant metabolism, photosynthesis, osmosis (movement of water in and out of plant cells) and ionic balance within the cell.

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#9

All of that is true, yes, but we’re talking to someone who is admitting that they don’t change their res. You can overdo sodium, just like you said, so I wouldn’t recommend that to anyone who admits they never change their res, lol.

5 Likes
#10

Yes your correct. You can poison your plants with too much sodium. Baking soda I’ve use a few times if I’ve added a little to much ph down into my rez but to be honest my rez is a gravity system and I run it until it’s empty, clean the rez then mix up a new batch of nutrients and it usually only takes a week for the plants to drink it all :+1:

3 Likes
#11

gravity system? it is like autopot?

I have the ph up stuff from ghe. Ok I am now wondering in which stages I should up the ph manually…

Any idea?

Maybe 0.2 stages? Like when I have 5.8 as starting point then maybe next time I up the ph to 6.0, then 6.2. And then lower it back to 5.8???

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#12

yes I admit, i am guilty of not changing the rez :wink:

1 Like
#13

It “IS” an autopot yes :v:

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#14

You can let it drift up to 6.4 without problems. Once it gets there you don’t just drop it back to 5.8 in one go as it will cause issues. Add a little ph down over a couple of days dropping the ph slowly until it gets to 5.4 ish then let it drift back up.

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#15

If you know what you are doing yes, if your new to growing it can cause alot of isues.
As long you can maintain your pH and NPK and micro nutes, you don’t need to do much res changes.

I only do hydro and I do very little water changing, I run a res for veg of my moms and then do 12/12 from clones.
So I don’t run veg and flower on the same res, if I did I would do a full res change about 2 weeks into flower.

For my flower res, if my Ec get’s too high I do 25% res change and see how that effects the Ec.
Again late in flower, when I wanna lower the Ec I do a 35-50% WC

For the most part, I just top it off every few days to keep the res full and adjust the pH.

My veg res I maybe do a res change 4 times a year, the rest of the time I just top off with pH adjusted water and add nutrients. At some point it will go out of ballance, the plants will tell me it’s time to change the res.

6 Likes
#16

Worth to mention!

If my pH starts skating all over, going up or down too fast and won’t stabalise.
I know it’s a lock out of something, might not show on the plants yet. In that case, I just change the res, rather then waiting to see the damage on the plants. In hope I can correct it, adding some N, P, K or what ever micronutrient is missing or too much of. Much easier and faster, to just mix up a new res you know got all it need in the right ratios.

5 Likes
#17

Same. Rez for moms and one rez for flower. No veg, only clones.

What you mean go out of balance? The ec is in right range but the dissolved nutrients have outbalanced ratio?

when it goes out of balance what signs the plants show?

I think the lower leaves going yellow are maybe magnesium, because the ph never drifts over 5.9…

4 Likes
#18

Deficiencys show up

Too much or too little of one nutrient, can lock out another nutrient and cause the pH to go out of ballance.

B7F3D93E-A371-4FF3-800B-9365AE4C984B.jpeg1022×1024 183 KB

Thats how it looks when you didn’t catch it in time, some things are easyer to catch then others.

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#19

Also maybe try to stop using pH up, a 5.7 pH is fairly spot on.
I run my flowering at 5.5 - 5.8, but let it drift up to 6.2 in the end to get them to yellow more.

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#20

Somehow I am not able to distinguish the different deficiencies on the graphic. :smiley:

Isn’t there a machine learning algorithm which does that job more accurate? :smiley:

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