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Rain water and tap water discussion

Spankee

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Regent pH testers are not that accurate. I recommend you get yourself a pH meter and learn how to use it before you start telling growers what to do with their water. 😎 Ask Google What is the most accurate way to test pH? Answer, pH meters are the most accurate type of measurement and are widely used. Google
Regent ph test are extremely accurate . I’m a swimming pool guy been in business over 30 years and Taylor test kits are the shit . You can even use a proof set to make sure your regents are good . Lamotte as well have some superior kits. Not arguing with meters but really your splitting hairs however test strips extremely inaccurate. Meters are great for instant gratification .
 

Creeperpark

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Regent ph test are extremely accurate . I’m a swimming pool guy been in business over 30 years and Taylor test kits are the shit . You can even use a proof set to make sure your regents are good . Lamotte as well have some superior kits. Not arguing with meters but really your splitting hairs however test strips extremely inaccurate. Meters are great for instant gratification .
OK thanks for the heads up friend. When testing my water with low ppm, my pH meter will give false readings. Regent pH tests will give good readings within a 5-point range using low ppm waters. 😎
 
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Creeperpark

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Damn CP! You're killing it my friend! I was just about to post about some issues I've been having(Shocker, I know), and I stumbled upon this gem of a thread.

Not sure if you recall, but I'm also a full time rainwater grower. I got a few concerns and a pretty unique situation. Could ya lend a brother some of that expertise?

Just to refresh..

The grow - 3 flower rooms and 1 veg room. Veg is mostly LED, flower is stacked 315 CDMs(Vertical). Plants start life in solos and move to 1G pots for the remainder. Medium is 6:1 perlite to vermiculite and the pots are setup hempy.

The reason I chose hempy is my water, or I should say, lack of. My well sucks(low pH, moderately hard, high Manganese and sodium). So I started a rainwater project right from the get go.

The water system - I have 3 275G tanks sistered together and a well pump in one that feeds a pretty typical residential type setup. It goes to a 33G pressure tank --> 2 stage sediment --> UV --> Carbon filter --> PEX runs to each res plus a few other outlets.

My problem is the old wavy tar roof causes me to miss a lot of water into the gutter and I'm under a bunch of trees which raises the ppm to around 30-40 in the spring/summer. I thought that adding bleach periodically to the tanks would help knock down whatever gets in my water in the spring(Its definitely something biological) and now my room misting units are leaving an almost salt like residue on the walls and floor.

So.......After all this I thought I would maybe run a line from the house to the grow(the well water) and blend that with the rainwater. Then I would run it through an RO setup. This way I solve both the lack of water and the quality issues in one shot. I know this isn't ideal, but I really, really need to move away from these damn hempys. All they do, IMO, is mess with the root zone. Remember, I only chose hempy cuz I don't have enough water......yet.

The only other option is for me to wait on the RO thing until I see what a new roof and gutter system will do for me. I'm redoing it with metal panels and a gutter on the second side so all in all I'll get a ton more water and it should be cleaner.......except for the damn trees above. Can't do anything there.

Sorry for the long-ass novel here. I just know you'll have some inspiring thoughts that'll help me put this all on a better path. I'm constantly plagued by issues mostly in veg. Depending on the strain, it'll be either something that looks like a Zinc issue or a stem purpling. I'm tired of wondering if my water is as good as it can be and I want to switch away from these hempys!

Thanks!!
There are a couple of things you can do that might help. One you can tack greenhouse plastic over the part of the roof that the rainwater falls on during rain and then remove it. You have to be careful because if it's not secured well the wind will blow it away. Second, you can use a window screen over the rain collection barrow for tree debris or even a cotton sheet as a sifting screen. As rain sets in the bucket dust falls in the water and raise the ppm. It doesn't bother me I use just plain rain. . 😎
 

ButterflyEffect

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There are a couple of things you can do that might help. One you can tack greenhouse plastic over the part of the roof that the rainwater falls on during rain and then remove it. You have to be careful because if it's not secured well the wind will blow it away. Second, you can use a window screen over the rain collection barrow for tree debris or even a cotton sheet as a sifting screen. As rain sets in the bucket dust falls in the water and raise the ppm. It doesn't bother me I use just plain rain. . 😎
I'm just gonna redo the roof this fall. I'll build a new frame over the existing one and tack on metal roof panels. Along with that, new gutter runs(I currently only have a gutter on one side). This way I get substantially more water per rain event and it'll be much, much cleaner!
 

Three Berries

Active member
Dumped the barrels and we had more rain so fresh rainwater. I use about 2 gallons a day. Mostly for the misters and one in flower.

Mine usually comes in at 20 ppm but I don't know how reliable my TDS meter was. I got a Apeara TDS20 one the other day but haven't used it. I bought three cheap ones off ebay and sent them back. Complete garbage and would not even agree with each other brand new in distilled water. When I went to measure the well water it was even worse.
 

Three Berries

Active member
I worked at a water bottler for a few years. Most of the water was RO, some natural spring water. Half the RO was mineral added. A few micrograms per gallon of potassium or magnesium carbonate. All the RO was city well water.

But they destroyed 1000s of gallons a week of old water or water in bad packaging. Might be a source for some if they have a plant near by.
 

Creeperpark

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This is one way I filter rainwater when it is hot and the ppm is around 40. I use an old cotton T-shirt.😎
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Creeperpark

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One thing for sure is changing the water in the middle of a grow is hard on plants. You would think that RO and rainwater could be equalized but they can't. Every time I have had to switch due to an unexpected drought I remember this. The rains are back now and I have fresh water (11ppm) again but the damage is already done. I'll pick up where I left off and run these on out on fresh rainwater. 😎

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Three Berries

Active member
I was using the cheap eBay ~$10 TDS meters. It broke so I ordered three more like it. None of them would read the same and in a concentrated mix they were off a lot it turns out. I ordered a Apera TDS 20 that is calibratable and the difference was shocking!
 

ButterflyEffect

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I was using the cheap eBay ~$10 TDS meters. It broke so I ordered three more like it. None of them would read the same and in a concentrated mix they were off a lot it turns out. I ordered a Apera TDS 20 that is calibratable and the difference was shocking!
I've been using an HM Digital com100 for 5 years now. Pretty rock solid. You're spot on about the crap chinese ones all ebay and whatnot. Total garbage. I sprung for an Apera AI209 and couldn't be happier. Been on pint for almost a year now.
 

acespicoli

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Thought id jump in with my experiences while I catch up on the thread :lurk:

rain water grows everthing on earth its the natural way of things, I have used rain water and it was better than the city water available.
One thing is to have a proper capture barrel that dumps the first run off that has all the dirt polllen bird poo etc
There is a device that automatically diverts the first portion of roof run off,

I can tell you that rain water contains a amount of atmospheric nitrogen thats helpful

Because rain droplets pass through the atmosphere on their way to the ground, rainwater also contains nitrogen in varying amounts. Although nitrogen is not a major component of oceans and land masses, it is an essential element for the formation of proteins in both plants and animals.

Petrichor is the smell of rain. The word comes from the Greek words 'petra', meaning stone, and 'ichor', which in Greek mythology refers to the golden fluid that flows in the veins of the immortals.


Rainwater is a mixed electrolyte that contains varying amounts of major and minor ions. Sodium, potassium, magnesium, calcium, chloride, bicarbonate, and sulfate ions are major constituents, to- gether with ammonia, nitrate, nitrite, nitrogen, and other nitroge- nous compounds (Hutchinson, 1957).
https://pubs.usgs. gov/wsp/1535g/report.pdf (link intentionally broken repair if interested in reading the report on rain water)

Spring beauty emerges from the forest floor in April.
It turns out the scent of spring is the very same substance responsible for the earthy taste of beets: a terpene known as geosmin. The name geosmin comes from the Greek words for “earth” and “smell.” Geosmin is produced by blue green algae and certain kinds of soil bacteria called actinomycetes. These bacteria break down plant material, and in the process convert another soil chemical (farnesyl diphosphate) to geosmin in a two-step process.


Geosmin exists in the soil year-round, but its smell is only noticeable under certain conditions—you might notice it when digging into soil, during spring thaw, and after a rain. This is because generally the gas pools in spaces beneath the soil surface and is only detectable when these pools are disturbed, like when digging turns over the soil or water soaks into it, displacing the gasses within. Sometimes the smell of geosmin is apparent before a storm hits, the result of decreasing pressure associated with the approaching weather causing the soils to off-gas geosmin and carbon dioxide that has built up beneath the surface.


With spring in full swing I hope you take the time to get out into the wild, where forests are coming to life and there is so much to see and explore. And while you are out there don’t forget to stop and smell the geosmin.




some good information in those links hopefully you have a min to browse them :) nice thread im glad you started this one thx
 
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Creeperpark

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Thank you Acespicoli, that's very helpful information. Lighting and other weather phenomena cause rainwater to be charged in a way that groundwater is not equal. When rain hits the ground it becomes the same as the ground and will cancel the electrolyte charge. IF you get the rain while the water is still charged with electrolytes you will be amazed at the plant's potential. I just harvested some fresh rainwater and the ppm is only 4 ppm. I filled up all my 5-gallon buckets with lids to keep the water fresh and low ppm. Rain water will stay fresh as the day it rains if you put a lid on the bucket. 😎
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Creeperpark

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Happy Day!!!! With the first watering using fresh rainwater, the plants responded in a positive way. When I switch to RO due to drought my plants showed a negative response. I felt a little sad because there was nothing I could do but use RO water for a couple of weeks. However, when I switched back to using fresh rain the plants perked up in 24 hr.

What is the difference between RO and rain? The difference is the water pH, because the RO water has already had the CEC canceled before being filtered. This means the pH is unnatural due to water treatment for basic tap water. Compared to rainwater which has high CEC capabilities RO lacks natural electrical conductivity. 😎
 

Creeperpark

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Starting pH of fresh rainwater is 5.5 pH. When you put rainwater on the soil the water converts to the soil pH quickly. I never have to use any acid or pH up using pure rainwater because of this conversion factor. To stablize the pH to a safer range I add a couple of ml of cal-mag to 3 gallons of water and let it set for a few hours. Then I recheck the pH and see that it's 6.5 to 6.9 pH and so I add General Hydroponics Flora series to bring the pH down lower to the desired pH. Just takes a little. So easy.😎
 
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Creeperpark

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So after the addition of fertilizer, the pH drops into the 6.2 to 6.5 pH range. I quickly water my plants because the buffer will push the pH above 7 after a few hours. The yo yo principle makes it easy for a plant to take what needs because it moves from 6.2 to over 7. pH in a few hours.

Another way is to not wait for the buffer to kick in and use lower pH water at 5.8 with fertilizers mixed in. Not waiting and using lower starting pH water gives a larger scale for nutrient absorption. After its all said and done the same amount of cal mag and fertilizer is used but the starting pH can be easily manipulated using rainwater. 😎
 
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Creeperpark

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RO water can't be done like the above because the pH has been disabled when it was treated at a water treatment plant. Only one watering with rainwater after using RO water for a while, I could see the plants responded much better. 😎
 
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ButterflyEffect

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RO water can't be done like the above because the pH has been disabled when it was treated at a water treatment plant. Only one watering with rainwater after using RO water for a while, I could see the plants responded much better. 😎
So, what would the CEC affect be on RO made from rain water? Or a blend of rain water and my well water? Does that effect still happen?
 

blondie

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First real rain in forever two days ago now. The rain water, at first, was a deep dark yellow color! I Dumped out many gallons until the water showed clear. I even sprayed the roof with hose water to clean before the rain. Didn’t seem to work.
 
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