Rainwater

TedeBoy

Well-Known Member
I use collected rainwater. It is 7.0 ph.
When I add my nutes the solution drops to 5.9.
I use "Ph Up" and bring it to 6.5.
I have them in a 50/50 mix of FFOF and FFHF.
Does the ph up or ph down products add salt?
I want to give them pure rainwater every so often. Should I ph down it or is 7.0 okay?

Should I get a TDS meter and what should my testing parameters be? I'm trying to not lock out any nutes by keeping ph and ppm in the correct range.
So far so good but I want to learn more.
 

hotrodharley

Well-Known Member
I use collected rainwater. It is 7.0 ph.
When I add my nutes the solution drops to 5.9.
I use "Ph Up" and bring it to 6.5.

Does the ph up or ph down products add salt?
I want to give them pure rainwater every so often. Should I ph down it or is 7.0 okay?

Should I get a TDS meter and what should my testing parameters be? I'm trying to not lock out any nutes by keeping ph and ppm in the correct range.
So far so good but I want to learn more.
Just add the nutes and use it.Don't add the pH Up. I use an EC meter in soil or hydro. It's very revealing seeing what the EC/PPM is when mixing per instructions. I start my soil feeds at a PPM of 250-300 the first feeding. I raise the next feed by 100-150. By then the plant will show what it needs and what it does not and adjust your nutes accordingly. By doing that I have fed PPM so high it would kill a normal plant because I raised the EC so gradually in a long veg. The last feeds I did before cutting for flowering were an EC of 2.4 or 1200 PPM.
 

TedeBoy

Well-Known Member
Just add the nutes and use it.Don't add the pH Up. I use an EC meter in soil or hydro. It's very revealing seeing what the EC/PPM is when mixing per instructions. I start my soil feeds at a PPM of 250-300 the first feeding. I raise the next feed by 100-150. By then the plant will show what it needs and what it does not and adjust your nutes accordingly. By doing that I have fed PPM so high it would kill a normal plant because I raised the EC so gradually in a long veg. The last feeds I did before cutting for flowering were an EC of 2.4 or 1200 PPM.
As far as pure rainwater goes 7.0 is okay?
 

hotrodharley

Well-Known Member
It's roof into a 205 gallon Bushman tank.
My last grow loved it.
I guess it depends on the roof and how often it rains.Do you filter it at all? Asking because of what unfiltered water collected that way could bring in like diseases. I'll bet it did love it.Best water there is in most cases. Great neutral base for feeds.
 

TedeBoy

Well-Known Member
I guess it depends on the roof and how often it rains.Do you filter it at all? Asking because of what unfiltered water collected that way could bring in like diseases.
That's a great point. Bird poop and dust in the initial fill after a dry spell.
I've thought about that some. This fill is after some rains but I guess I do run the risk.
 

hotrodharley

Well-Known Member
That's a great point. Bird poop and dust in the initial fill after a dry spell.
I've thought about that some. This fill is after some rains but I guess I do run the risk.
http://www.instructables.com/id/How-to-made-a-cheap-homemade-water-filter/

You will see the sound principle and can make a bigger one etc. If you made one with a 5-gallon bucket you could get a usable volume of water pretty quickly. A few drops of Clorox will kill any critters and a FEW drops will not hurt anything. In fact add the Clorox to the raw water and then filter it.
 

TedeBoy

Well-Known Member
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http://www.instructables.com/id/How-to-made-a-cheap-homemade-water-filter/

You will see the sound principle and can make a bigger one etc. If you made one with a 5-gallon bucket you could get a usable volume of water pretty quickly. A few drops of Clorox will kill any critters and a FEW drops will not hurt anything. In fact add the Clorox to the raw water and then filter it.
ive just collected rain from the roof into a bucket from there i bottle them with the cap's off and i never had a problem

i never thought to filter it n bleach it...i guess ill have to do this next time thanks very much
 
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Nullis

Moderator
When it comes to roof-runoff collected rainwater it really depends on several factors. Where you live, the season, how frequently it rains, rain quality, roofing materials and how frequently it rains. Pollen, bird crap, sure and all kinds of other shit accumulates on roofs. The less frequently it rains the more debris will accumulate for sure.

So ideally for rainwater collection (especially with larger tanks for storage) you would have what they call a first flush diverter. These are designed to expel rather than collect an initial volume of water, based on the size of the roof.
http://arkitrek.com/http:/arkitrek.com/first-flush-diverter/
 
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