Water Above 14ppm: Full pH Swing Discussion Thread

Hey everyone,

I would like a simple and easy way for you to be able to diagnose your tap water for a full pH swing. Since nearly every source of unfiltered tap water is different, the pH responses are all different. I know, with enough info posted by enough growers, we can come up with a basic method which will be very helpful.

PLEASE, if it is safe to post your water report details please do so! Your information will be much more helpful to everyone if the makeup of your water is included.

Helpful information to include in your post:
WATER REPORT (Plus seasonal differences if any)
Light wattage and type
Nutrients being used
Number of plants and size
Volume of nutrient solution in reservoir
High/Low/Average Temps
High/Low/Average rH
Air pump/stone information
Liters/min or wattage/type of airpump

Helpful information to track:
Starting pH/ppm
Daily change in pH/ppm
How often you add pH up/down
How often you add nutrients
Transpiration rate (amount or rate of water usage each day)
Stage in flower

Last but not least:
Please note your efforts and/or successes so far with any details you believe may be important to others.

Thank you!

Douglas.Curtis said:

Hey everyone,

I would like a simple and easy way for you to be able to diagnose your tap water for a full pH swing. Since nearly every source of unfiltered tap water is different, the pH responses are all different. I know, with enough info posted by enough growers, we can come up with a basic method which will be very helpful.

PLEASE, if it is safe to post your water report details please do so! Your information will be much more helpful to everyone if the makeup of your water is included.

Helpful information to include in your post:
WATER REPORT (Plus seasonal differences if any)
Light wattage and type
Nutrients being used
Number of plants and size
Volume of nutrient solution in reservoir
High/Low/Average Temps
High/Low/Average rH
Air pump/stone information
Liters/min or wattage/type of airpump

Helpful information to track:
Starting pH/ppm
Daily change in pH/ppm
How often you add pH up/down
How often you add nutrients
Transpiration rate (amount or rate of water usage each day)
Stage in flower

Last but not least:
Please note your efforts and/or successes so far with any details you believe may be important to others.

Thank you!

Click to expand...

Ok. This is exactly my setup and exactly what I just experienced in the last month.


Water Report - Don't have one other than tap water is 218ppm. Calcium is 65ppm of the 218. Would be classified as very hard water.
Light watt/type - 1000w Metal halide, Philips MH1000 lamp, protected for open fixture rating, good UV output, 3800k
Nutrient being used - GH Hardwater Floramicro/series 3 part, cal mag
# of plants and size - 4 plants, 2-3ft in height and width. Good sized stems.
Volume of water in reservoir - Not sure if this is the total volume of the system or just the volume of the control bucket?
High low temps - 77 degress F
High low humidity - Didn't measure, but probably 40RH.
Air pump/stone - 50L/min pump, special, circular air diffusers(for aquariums)


Starting pH/ppm - 5.5, 500-600ppm.
Daily change in pH/ppm - Slow daily raise - about .8 (6.1) after a week and a half. Unable to accurately get ppm change, with high water usage. I'm guessing they're using about as much nutrient as water, as the ppm's remain more or less stable despite 5 gallons of water loss.
How often add ph up/down - pH down when doing nutrient top offs or complete system changes. Currently every 3 days.
Brand of pH down - Bumper crop - Phosphoric acid.
How often add nutrients - When doing top offs or complete system changes. Currently every 3 days.
Transpiration rate - HIGH. unsustainable almost without auto makeup system. Nearly 5 gallons every two/three days.
Stage in flower - Still in veg!


All i can say is after a month of this system (and being new to hydroponics) with hard tap water, GH Hardwater Floramicro works to keep the pH in an acceptable range. If you have high transpiration rates, you might want an auto nutrient makeup system as the top offs are nearly problematic because of the frequency (when the plants get bigger). Any pH drift happens slowly with this nutrient, in this system...no opportunity to allow for any significant drift. If you wanted to incorporate more of a drift, at these transpiration rates....you would have to implement it into your top offs.


Here's a link to this grow: https://www.icmag.com/ic/showthread.php?t=372097

Be filling this out in a day or so

Substitute said:

Volume of water in reservoir - Not sure if this is the total volume of the system or just the volume of the control bucket?

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Should be total volume of solution in your reservoir, not volume of entire reservoir.

A 1000w lamp needs 45-50 gallons of nutrient solution. At max flower in a 4x4 space, 6 plants will use up to 5 gallons of water per day during peak flower production. Be prepared.

Substitute said:

High low temps - 77 degress F
High low humidity - Didn't measure, but probably 40RH.

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Moderate transpiration then, and about right for a decent run.

Substitute said:

Starting pH/ppm - 5.5, 500-600ppm.
Daily change in pH/ppm - Slow daily raise - about .8 (6.1) after a week and a half. Unable to accurately get ppm change, with high water usage. I'm guessing they're using about as much nutrient as water, as the ppm's remain more or less stable despite 5 gallons of water loss.

Click to expand...

Always check pH/ppm when conditions are the same. I use the nutrient level as my guide by topping off the reservoir once a day to the same level. Once the reservoir is "full" to the mark I check pH and ppm. Without doing this your readings will not be useful for tracking changes.

500 is too low for 1000W, which explains why you're seeing a steady ppm as the plants straight up drink that water. You'll most likely find better growth and health between 600 and 650, at least on a .5 ppm meter. I believe there are still some .7's out there.

Substitute said:

How often add ph up/down - pH down when doing nutrient top offs or complete system changes. Currently every 3 days.
Brand of pH down - Bumper crop - Phosphoric acid.
How often add nutrients - When doing top offs or complete system changes. Currently every 3 days.

Click to expand...

This is where you're going to do most of your work on figuring out your tap water. Once you're checking daily after top-offs you'll have useable data in about a week. Your goal is to get a natural swing, so you're adjusting pH when you first mix the res and hopefully not again till near harvest. Keeping the water level the same and adding back nutrients should drop your pH to your starting point. Again, this is going to be very specific for your water.

Remember to focus on taking and tracking your readings when the res is topped off. You'll get a much clearer picture of what's going on rather quickly.

If you're not at 45-50 gallons of nutrient solution I would look at increasing your res size if at all possible. It will make your plants a whole lot happier and your life a whole lot easier. My 1K gardens are mostly work at setup and harvest, because the rest of the time I'm taking only a few minutes to top off, check pH/ppm and make sure the plants are healthy and bug free. Almost no work till near harvest.

Douglas.Curtis said:

Should be total volume of solution in your reservoir, not volume of entire reservoir.

A 1000w lamp needs 45-50 gallons of nutrient solution. At max flower in a 4x4 space, 6 plants will use up to 5 gallons of water per day during peak flower production. Be prepared.

Moderate transpiration then, and about right for a decent run.


Always check pH/ppm when conditions are the same. I use the nutrient level as my guide by topping off the reservoir once a day to the same level. Once the reservoir is "full" to the mark I check pH and ppm. Without doing this your readings will not be useful for tracking changes.

500 is too low for 1000W, which explains why you're seeing a steady ppm as the plants straight up drink that water. You'll most likely find better growth and health between 600 and 650, at least on a .5 ppm meter. I believe there are still some .7's out there.


This is where you're going to do most of your work on figuring out your tap water. Once you're checking daily after top-offs you'll have useable data in about a week. Your goal is to get a natural swing, so you're adjusting pH when you first mix the res and hopefully not again till near harvest. Keeping the water level the same and adding back nutrients should drop your pH to your starting point. Again, this is going to be very specific for your water.

Remember to focus on taking and tracking your readings when the res is topped off. You'll get a much clearer picture of what's going on rather quickly.

If you're not at 45-50 gallons of nutrient solution I would look at increasing your res size if at all possible. It will make your plants a whole lot happier and your life a whole lot easier. My 1K gardens are mostly work at setup and harvest, because the rest of the time I'm taking only a few minutes to top off, check pH/ppm and make sure the plants are healthy and bug free. Almost no work till near harvest.

Click to expand...

Thanks for the reply Doug. I built my system exactly like other systems I saw on the market. 5 buckets. 4 for growing and 1 control bucket where you do all the water changes, top off's, etc. RDWC. Total system volume is 25 gallons...control bucket is obviously 5 gallons.

I have another 150 gallon reservoir that I use to store my water. It isn't connected to the system. It holds my chlorinated water until use for top offs, etc.

I'm running 575ppm's on average for nutrient.

Now, you don't use RDWC...so some of the semantics are confusing my understanding of your post. Is your main 'holding res', the 45-50 gallons, full of premixed nutrient or do you mix the nutrient every day to add? Because you're DWC...you have no control bucket...so I'm assuming your big res is separate (like my big res is).

I don't have room for a bigger control bucket or control res...whatever the term is...but I need to figure something out...because I don't want to have to add back all this nutrient/water, etc every couple days. I have a float valve installed in my control bucket for this very purpose, but it isn't hooked to anything yet.

Substitute said:

I'm running 575ppm's on average for nutrient.

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This is with all the ppm from your water, yes?

Substitute said:

Now, you don't use RDWC...so some of the semantics are confusing my understanding of your post. Is your main 'holding res', the 45-50 gallons, full of premixed nutrient or do you mix the nutrient every day to add? Because you're DWC...you have no control bucket...so I'm assuming your big res is separate (like my big res is).

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I typically use 45-50 gallons of nutrient solution in a 70 gallon reservoir for a 4x4 space. It's one giant tub with airstones in it, and a supported cover for 6" netpots.

As described in my other thread with r/o water, I mix to full strength and adjust pH to lowest healthy point. When your mix is the correct strength for your conditions, you will see the ppm go down and the pH rise as time passes. It's the change in pH over time which will have the largest difference for you according to what is in the tap water and which parts of your nutrient mix it's messing with (if any).

You want a rise from 5.4 to 6.0 in about 7 days with a full reservoir. pH rising too fast? Use a larger reservoir. Too slow? Use fewer gallons at a time in the same res or increase canopy and lamp size.

Substitute said:

I don't have room for a bigger control bucket or control res...whatever the term is...but I need to figure something out...because I don't want to have to add back all this nutrient/water, etc every couple days. I have a float valve installed in my control bucket for this very purpose, but it isn't hooked to anything yet.

Click to expand...

I do know 25 total gallons does not hold enough water or nutes for a regular and full pH swing like I'm used to. I add back up to 5 gallons of water a day at peak flower so not sure what that would do to your schedule with half that.

I would think about plumbing in a larger reservoir, no? Either way I'm sure you'll figure something out. You ask very good questions so... that helps.

Douglas.Curtis said:

This is with all the ppm from your water, yes?


I typically use 45-50 gallons of nutrient solution in a 70 gallon reservoir for a 4x4 space. It's one giant tub with airstones in it, and a supported cover for 6" netpots.

As described in my other thread with r/o water, I mix to full strength and adjust pH to lowest healthy point. When your mix is the correct strength for your conditions, you will see the ppm go down and the pH rise as time passes. It's the change in pH over time which will have the largest difference for you according to what is in the tap water and which parts of your nutrient mix it's messing with (if any).

You want a rise from 5.4 to 6.0 in about 7 days with a full reservoir. pH rising too fast? Use a larger reservoir. Too slow? Use fewer gallons at a time in the same res or increase canopy and lamp size.


I do know 25 total gallons does not hold enough water or nutes for a regular and full pH swing like I'm used to. I add back up to 5 gallons of water a day at peak flower so not sure what that would do to your schedule with half that.

I would think about plumbing in a larger reservoir, no? Either way I'm sure you'll figure something out. You ask very good questions so... that helps.

Click to expand...

No. That's 575ppm of just nutrient. It would be ~ 793ppm with the original water hardness added (218ppm).

There's no room or opportunity for my system pH to drift...as I'm re-adding pH down, nutrient, etc...after only a few days. Regardless, last time I added the pH was slightly higher...so there is an ipso facto drift happening. I can add whatever pH - top off I like so. I can go slightly higher each time if I want.

Maybe I can plumb in an additional 25 gallon res...and auto feed nutrient into the float valve on the control bucket somehow. That would make it so I could leave it for a while.

Ok, that makes more sense. The extra ppm in your water is going to make a big difference in the end. The 200ppm in your water could be additional nutes dropping the pH and eliminating your need for pH down. You're going to be amazed when you switch to r/o.

I would definitely plumb in an extended res. I don't grow the way others do, and I have great difficulty finding similar quality from others. Even in the great state of Colorado.

On a side note related to your comment on the current hydro 'basics' in the industry, I'm currently working on a mechanical engineering degree and have a lot of ideas about equipment I'm going to design in the future. I look at the hydro equipment industry and, from my perspective, there's sooooo much missing and sooo much wrong.

Have you tried

Douglas.Curtis said:

Ok, that makes more sense. The extra ppm in your water is going to make a big difference in the end. The 200ppm in your water could be additional nutes dropping the pH and eliminating your need for pH down. You're going to be amazed when you switch to r/o.

I would definitely plumb in an extended res. I don't grow the way others do, and I have great difficulty finding similar quality from others. Even in the great state of Colorado.

On a side note related to your comment on the current hydro 'basics' in the industry, I'm currently working on a mechanical engineering degree and have a lot of ideas about equipment I'm going to design in the future. I look at the hydro equipment industry and, from my perspective, there's sooooo much missing and sooo much wrong.

Have you tried

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Hey Doug. I don't know if I will switch to r/o. It's too expensive and too wasteful. With General Hydroponics Hardwater series...who needs r/o? Maybe you'll switch to tap water.

I'm pretty happy so far with the system I built...other than the small control res/bucket. I'm diggin the air diffusers pumpin out the small bubbles...and the pump is fairly quiet. pH is at 5.6..started at 5...after 3 days topped off with slightly higher pH...so I could just continue like this topping off with slightly higher pH to create a drift.

I will try to increase the size of the control res.

Substitute said:

Hey Doug. I don't know if I will switch to r/o. It's too expensive and too wasteful. With General Hydroponics Hardwater series...who needs r/o? Maybe you'll switch to tap water.

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Forget the GH hardwater nutes and switch to their Dry Maxi-Grow and Maxi-Bloom. Works great in Tap. Don't waste money buying water. Check out the KISS thread here for Maxi-Bloom

RockinRobot said:

Forget the GH hardwater nutes and switch to their Dry Maxi-Grow and Maxi-Bloom. Works great in Tap. Don't waste money buying water. Check out the KISS thread here for Maxi-Bloom

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Quickly checked out the specs on Maxigrow and bloom and they sound good. Right now i'm using the Flora series but if the Maxi-series is more cost effective I'll look into it. I'd probably want the 16lb containers to start with.

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Quickly checked out the specs on Maxigrow and bloom and they sound good. Right now i'm using the Flora series but if the Maxi-series is more cost effective I'll look into it. I'd probably want the 16lb containers to start with.

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I run 2 bays staggered 6 weeks apart with a 12 week flower cycle. Each bay has a 20g reservoir which I change weekly and the 2lb bag lasts a full grow on both bays with leftover. So I basically get 2+ crops per 2lb bag for $16 in nutrients. Was paying $12/bottle for the 3 part when I was using that. That equates to $36 for 2 grows and it's all water and bottling that you pay extra for.

RockinRobot said:

I run 2 bays staggered 6 weeks apart with a 12 week flower cycle. Each bay has a 20g reservoir which I change weekly and the 2lb bag lasts a full grow on both bays with leftover. So I basically get 2+ crops per 2lb bag for $16 in nutrients. Was paying $12/bottle for the 3 part when I was using that. That equates to $36 for 2 grows and it's all water and bottling that you pay extra for.

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At the rate i'm using nutrients now that sounds like a big savings.

Substitute said:

Hey Doug. I don't know if I will switch to r/o. It's too expensive and too wasteful. With General Hydroponics Hardwater series...who needs r/o? Maybe you'll switch to tap water.

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It's wasteful only if you waste the water, it's ridiculously inexpensive to buy a filter because they're generally under $200 and a small grow will change filters less than once a year.

I prefer super clean burning cannabis, so I'll definitely use tap water when I live somewhere it's <14ppm.

I got a used RO 5 stage kit used for $50 and $45 for all new filters.

Douglas.Curtis said:

It's wasteful only if you waste the water, it's ridiculously inexpensive to buy a filter because they're generally under $200 and a small grow will change filters less than once a year.

I prefer super clean burning cannabis, so I'll definitely use tap water when I live somewhere it's <14ppm.

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"A reverse osmosis system wastes about 4 gallons of water per gallon made. If you use 3 gallons a day for drinking, cooking and internal consumption, that means you will waste about 12 gallons, making a reverse osmosis system about 25% effecient! ... A reverse osmosis system is 25% efficient."


Terrible!

Substitute said:

"A reverse osmosis system wastes about 4 gallons of water per gallon made. If you use 3 gallons a day for drinking, cooking and internal consumption, that means you will waste about 12 gallons, making a reverse osmosis system about 25% effecient! ... A reverse osmosis system is 25% efficient."


Terrible!

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Who is trying to sell you What?

If you're interested in the facts:
With a 1:1 restriction flow valve, you create about 1 gallon of hard(er than your tap water) water per gallon of r/o water.

IF you dump these gallons down the drain they are wasted. When you collect them and use them to water your garden, wash your car, water your lawn... it is not wasted.

Again, whoever wrote what you copied is either selling something or woefully ignorant and loud.

Douglas.Curtis said:

Who is trying to sell you What?

If you're interested in the facts:
With a 1:1 restriction flow valve, you create about 1 gallon of hard(er than your tap water) water per gallon of r/o water.

IF you dump these gallons down the drain they are wasted. When you collect them and use them to water your garden, wash your car, water your lawn... it is not wasted.

Again, whoever wrote what you copied is either selling something or woefully ignorant and loud.

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That's why we created this thread! There are some really good Hardwater (tap water) nutes available!

Actually, the purpose of this thread was to develop some sort of method tap water users could use to figure out their pH swing. Doesn't look like it's going to happen though and I'm involved in far too much schooling to be of much help.

I'll have a bit of time in a few weeks before fall semester starts.

Hey Douglas.Curtis,
IMO you are trying to hard for nothing. You seem to just attract people who want to tell you that you are wrong in some way or another. I always enjoy reading info from you but honestly it feels like you are being trolled. Good luck and happy harvesting