How to mix nutes for hydro

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Dankness420

Dankness420

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There are better options than baking soda like potassium bicarbonate but I'm assuming you don't have that on hand. It's very cheap to order and that way you can avoid the sodium uses in baking soda.

But both work well
Thank you so much for this I will give it a go! The potassium bicarbonate do I get at any plant store? And how much do I use if not the same amount? I'm gonna head out to to try and find the potassium bicarbonate and if I dont find it I have some baking soda
 
Aqua Man

Aqua Man

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Thank you so much for this I will give it a go! The potassium bicarbonate do I get at any plant store? And how much do I use if not the same amount? I'm gonna head out to to try and find the potassium bicarbonate and if I dont find it I have some baking soda

you can order it online. I would start at 1/4tsp with the potassium bicarbonate
 
MIMedGrower

MIMedGrower

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Im sorry if this is a bit off topic. @Aqua Man knows his hydro and i have a question. When we add nutes to the res the ph likely goes down. I havent tried hydro but i am guessing if the mixture is say 1.2 ec and 5.5 ph I would leave it there. Then this is the part i understand a bit different than you explained about buffering.

As the plant uptakes the nutes the ph in the res would rise. Im going to say if proper ec this would happen over a week and then i would add new nutes with a res change and the ph would go back down.

Isnt this a natural cycle for the plants. And dont they do better with a gradual swing up in ph to ensure uptake of all elements?

Or is the object to het the res ph to stay rick steady?

Or do both work?

Thank you and back to the regularly scheduled programming.....
 
Aqua Man

Aqua Man

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Im sorry if this is a bit off topic. @Aqua Man knows his hydro and i have a question. When we add nutes to the res the ph likely goes down. I havent tried hydro but i am guessing if the mixture is say 1.2 ec and 5.5 ph I would leave it there. Then this is the part i understand a bit different than you explained about buffering.

As the plant uptakes the nutes the ph in the res would rise. Im going to say if proper ec this would happen over a week and then i would add new nutes with a res change and the ph would go back down.

Isnt this a natural cycle for the plants. And dont they do better with a gradual swing up in ph to ensure uptake of all elements?

Or is the object to het the res ph to stay rick steady?

Or do both work?

Thank you and back to the regularly scheduled programming.....
No you want ph to rise... However you want it to rise slowly if the ph is jumping up in 24 hrs by 1 point then your dropping it back down that's stressful to the plant as the ph swing is way to much.

You right the nutrient uptake will generally cause ph to rise. I think this is mostly due to nitrogen uptake but can't remember. But also the acid breaks down. So if it's rising that fast it's not good.

Think of it like RO water no alkalinity (no buffering capacity) so very little acid needed to lower ph. Nutrients are also generally acidic so even less is needed. So you have a very small acidic influence causing a decent ph change. As the nutrients are taken up and the acid breaks down since there is so little (think ppm wise say 50ppm) say half the acidic contribution breaks down or taken up (25ppm) which in this case isn't much that equally increases ph by percentage so say 50% increase to starting ph. Now if you have more alkalinity and require more acid to bring the ph down (say now 200ppm) and you take away that uptake and acid breakdown of 25ppm the change to ph is much smaller. So basically the more alkalinity you start with the more acid needed to adjust and the more stable the ph is. Ideally you want 0.2-0.3 a day. This allows nutrient uptake over a varying ph but still providing stability. To much alkalinity and like you say you have a brick and it's just not suitable. Also the increased levels of acid and what used for alkalinity can have negative effects of to high of concentrations are used.

This is kinda of an analogy answer.
 
MIMedGrower

MIMedGrower

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438
No you want ph to rise... However you want it to rise slowly if the ph is jumping up in 24 hrs by 1 point then your dropping it back down that's stressful to the plant as the ph swing is way to much.

You right the nutrient uptake will generally cause ph to rise. I think this is mostly due to nitrogen uptake but can't remember. But also the acid breaks down. So if it's rising that fast it's not good.

Think of it like RO water no alkalinity (no buffering capacity) so very little acid needed to lower ph. Nutrients are also generally acidic so even less is needed. So you have a very small acidic influence causing a decent ph change. As the nutrients are taken up and the acid breaks down since there is so little (think ppm wise say 50ppm) say half the acidic contribution breaks down or taken up (25ppm) which in this case isn't much that equally increases ph by percentage so say 50% increase to starting ph. Now if you have more alkalinity and require more acid to bring the ph down (say now 200ppm) and you take away that uptake and acid breakdown of 25ppm the change to ph is much smaller. So basically the more alkalinity you start with the more acid needed to adjust and the more stable the ph is. Ideally you want 0.2-0.3 a day. This allows nutrient uptake over a varying ph but still providing stability. To much alkalinity and like you say you have a brick and it's just not suitable. Also the increased levels of acid and what used for alkalinity can have negative effects of to high of concentrations are used.

This is kinda of an analogy answer.


Got it. You buffer the solution enough that it rises slowly over time.
 
Aqua Man

Aqua Man

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Got it. You buffer the solution enough that it rises slowly over time.
Kinda why I feel dirtbag may be having issues. In soil we have these buffers already added in hydro we need to add and adjust. Even with the changing feed strengths. With a 1 part nutrient it limits the sources and it's likely very low in alkalinity then he is using RO water. His EC is increasing which should lower ph usually. But depending what the plants taking up it could do the opposite as any change in nutrients will have a larger affect on the ph. Even with mega crop at low doses using RO I needed to add some potassium bicarbonate until my EC was higher. I also seem to remember something about acid reacting to rockwool? Add the CEC exchange and although I'm not positive I kinda feel it's likely that if he increased the starting alkalinity and ph'ed down it may solve his issue. But I hinted a bit at it in his thread and others may have a better idea. I have never used rockwool
 
FourthCity

FourthCity

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My reservoirs ph keep going up, I ph it and the next day it goes from 6. Whatever to the 7s, why is that happening? My drippers are on 24/7, I gave the plant mild nutes like 2 days ago for the first time at 1/4 strength, my plants are yellow now I dont know why, I checked my ppm and one of the reservoirs is steady the other one went from 230ppm to 306ppm, can anyone help with this? My tap water has a ppm of 90 on it's own, and i haven't used any calmag yet should i? Man should have grown in soul this is difficult haha
I agree with Aquamans suggestions to treat your ph issue but I believe at least one of the reasons for the spiking you are seeing is the hydroton. It has a naturally higher ph and will gradually effect the reservoir as the water continuously drips through it. Over time the pebbles will stabilize and you should see less fluctuations.
 
Aqua Man

Aqua Man

26,480
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I agree with Aquamans suggestions to treat your ph issue but I believe at least one of the reasons for the spiking you are seeing is the hydroton. It has a naturally higher ph and will gradually effect the reservoir as the water continuously drips through it. Over time the pebbles will stabilize and you should see less fluctuations.
I have actually tested the ph influence of hydroton. It's inert in my experience however there are many brands so it possible that it could be an issue. To test this simply take and rinse some new hydroton and rinse it well then place a few pieces in a cup of RO water. With RO any change to ph will be very pronounced and you will be able to verify if infact your hydroton may be altering ph. But understand that if it's changing the ph you would then need to see how much influence it has after to determine if it could influence the volume of the res.
 
FourthCity

FourthCity

778
143
This is a close up, first time using a drip system tbh so any help would do. I have read ppl saying to keep it on 24/7 and some ppl to time it, I'm using expanded clay peoples and seed was started in a rooting sponge soaked in tap water only
Did your rooting sponge have roots sticking out before being transplanted to the net pots? If so you should be fine leaving the dripper on 24/7, if you didnt have some roots already I would recommend a timer that alternates on and off at hour intervals. This will give the plant a chance to dry a little more and promote early root growth.
 
FourthCity

FourthCity

778
143
I have actually tested the ph influence of hydroton. It's inert in my experience however there are many brands so it possible that it could be an issue. To test this simply take and rinse some new hydroton and rinse it well then place a few pieces in a cup of RO water. With RO any change to ph will be very pronounced and you will be able to verify if infact your hydroton may be altering ph. But understand that if it's changing the ph you would then need to see how much influence it has after to determine if it could influence the volume of the res.
Im not sure how or why it works (the science behind it) but I suspect its like how rockwool is inert yet also can cause ph fluctuations if not treated. Perhaps the clay itself is inert but the pebbles are becoming saturated in alkaline minerals? I always rinse new hydroton extensively with tap water to get out all the sandy bits of clay and afterwards I soak it in ph'd tap water, I test the water for changes and and replace it daily until I no longer see any significant spiking, this usually takes a few days. I have not tested this like you mentioned with RO water. I'm thinking that the ro vs tap water might explain some of our different experiences.
 
Dankness420

Dankness420

95
18
Im sorry if this is a bit off topic. @Aqua Man knows his hydro and i have a question. When we add nutes to the res the ph likely goes down. I havent tried hydro but i am guessing if the mixture is say 1.2 ec and 5.5 ph I would leave it there. Then this is the part i understand a bit different than you explained about buffering.

As the plant uptakes the nutes the ph in the res would rise. Im going to say if proper ec this would happen over a week and then i would add new nutes with a res change and the ph would go back down.

Isnt this a natural cycle for the plants. And dont they do better with a gradual swing up in ph to ensure uptake of all elements?

Or is the object to het the res ph to stay rick steady?

Or do both work?

Thank you and back to the regularly scheduled programming.....
This is an amazing question actually, mine was fluctuating on a daily basis unfortunately
 
Dankness420

Dankness420

95
18
Did your rooting sponge have roots sticking out before being transplanted to the net pots? If so you should be fine leaving the dripper on 24/7, if you didnt have some roots already I would recommend a timer that alternates on and off at hour intervals. This will give the plant a chance to dry a little more and promote early root growth.
Yes it did have roots sticking out the sides, not many but it did have a few
 
Dankness420

Dankness420

95
18
I agree with Aquamans suggestions to treat your ph issue but I believe at least one of the reasons for the spiking you are seeing is the hydroton. It has a naturally higher ph and will gradually effect the reservoir as the water continuously drips through it. Over time the pebbles will stabilize and you should see less fluctuations.
I actually do believe its cause of the clay rocks, I use clay rocks and hydro tons in the other ( one is orange and one looks like rocks) the orange ones cause the ph to rise more than the other ones, I did rinse and soak for 24hrs, but i do believe that's at least one of my issues
 
Aqua Man

Aqua Man

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I actually do believe its cause of the clay rocks, I use clay rocks and hydro tons in the other ( one is orange and one looks like rocks) the orange ones cause the ph to rise more than the other ones, I did rinse and soak for 24hrs, but i do believe that's at least one of my issues
Easy to test and find out. While it can contribute I cant see it being responsible for a spike that big. I would say your ph is not stable but it could be contributing if that's the case. Are you finding this ph rise in both?

And if it is contributing I would stop using it.
 
FourthCity

FourthCity

778
143
Easy to test and find out. While it can contribute I cant see it being responsible for a spike that big. I would say your ph is not stable but it could be contributing if that's the case. Are you finding this ph rise in both?

And if it is contributing I would stop using it.
The spikes are consistent with what I've seen washing new hydroton, but again this always eventually stabilized. I reuse old hydroton and only have this issue when it is brand new. Aquaman, I only used ro water for a couple grows but one thing I noticed is that without making any adjustment the ph would drop a point or two over about a week where my tap water tended to only drop about a half a point. I think this might offset some spiking for those that are using ro water. I'm thinking the hydroton is acting like a catalyst with different outputs depending on the input.
 
Aqua Man

Aqua Man

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638
The spikes are consistent with what I've seen washing new hydroton, but again this always eventually stabilized. I reuse old hydroton and only have this issue when it is brand new. Aquaman, I only used ro water for a couple grows but one thing I noticed is that without making any adjustment the ph would drop a point or two over about a week where my tap water tended to only drop about a half a point. I think this might offset some spiking for those that are using ro water. I'm thinking the hydroton is acting like a catalyst with different outputs depending on the input.
If your ph is dropping there is an issue. Usually root rot or your nutes are way to high and the ppm is increasing. This can happen if you don't do daily top ups.
 
FourthCity

FourthCity

778
143
If your ph is dropping there is an issue. Usually root rot or your nutes are way to high and the ppm is increasing. This can happen if you don't do daily top ups.
I was describing what I noticed just with tap water and ro water in separate buckets, no plants, no nutes, no ph adjustments, no other variables. I tested this because I found when I was using the ro water (specifically early in veg) the ph would slightly drop over time from where I had adjusted it and with tap water it either stayed the same or slightly rose. After some research just now I think I found some relevant info:

"Because reverse osmosis removes the minerals in water the water will then react with carbon dioxide upon exposure to air to form carbolic acids, thus lowering the pH. The resultant pH will depend on the initial water chemistry. It cannot be predicted. "

and more technical

"When water is passed through a semi permeable membrane using pressure, many organic and inorganic compounds fail to pass through, however gases like Carbon Dioxide make it to the other side. CO2 combines with the free OH- ions in water to form acidic HCO3, while the H+ ions fail to find any substance to interact with as most of the impurities have been removed through the RO process.

CO2 + H2O <--> H+ + HCO3-

As a result, water has a positive balance of H+ ion, lowering its pH and making it acidic. (Again, remember, pH is measure of H+ with a minus. No more chemistry further, we promise!). The greater the amount of CO2 in your water, the greater is the drop in pH level"
 
V

Vondank420

184
63
All great info by AquaMan and the THC crew.
I have a possible solution. You can use it as it works fantastic or file in under T for trash...

Build a simple top off rez with a 5gal bucket.
Use 3/8" quick fittings and put a float in the aquafarm. Run a line from the bucket to the float and your dialed. You can mix any amount up to 5 gals. This is alot easier on the plants than making manual PH inputs. We do this same thing on scale
We run our nutes in the top off rez 10% stronger and 5.6
Anyway good luck. Look forward to seeing moster bush...
 
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